The Cherokee Nation of Oklahoma (“Cherokee Nation”) and Delaware Tribe of Indians (“Delawares”) entered into a contract pursuant to a treaty negotiated between the Cherokee Nation and the United States Government. The Supreme Court has twice interpreted that contract. We must deeide in this case whether the Department of Interior’s (“DOI”) interpretation of that contract and concomitant decision to extend Federal recognition to the Delawares is contrary to the Supreme Court’s reading of the same document.
I.
The law governing Federal recognition of an Indian tribe is, today, clear. The Federally Recognized Indian Tribe List Act of 1994 provides Indian tribes may be recognized by: (1) an “Act of Congress;” (2) “the administrative procedures set forth in part 83 of the Code of Federal Regulations!);]” or (3) “a decision of a United States court.” Pub.L. No. 103-454, § 103(3), 108 Stat. 4791; see also United Tribe of Shawnee Indians v. United States, 253 F.3d 543, 547-48 (10th Cir.2001). A recognized tribe is placed on the DOI’s “list of recognized tribes[.j” 25 U.S.C. §§ 479a(3), 479a-l; 25 C.F.R. § 83.5(a).
The Delawares had never been on the list prior to this lawsuit. The Delawares began a quest for Federal recognition in 1992. They submitted a letter to the DOI expressing an intent to petition for Federal acknowledgment under the “Part 83 procedures.” See 25 C.F.R. §§ 83.1, 83.4. The DOI informed the Delawares it would not consider their petition. The agency explained the “Delawares have not existed as an independent political identity since *10771867, and have been absorbed into the Cherokee Nation of Oklahoma for general governmental purposes since that time.” The Delawares, in response, requested instructions for filing an appeal. The DOI thereafter reaffirmed its position, but “clarified” its previous non-appealable advisory letter did not prevent the Delawares from petitioning under the Part 83 procedures.
The Delawares never formally petitioned for acknowledgment. Instead, they requested the DOI to “reconsider and retract” the agency’s position, as expressed in a 1979 letter, that it would only engage in government-to-government relations with the Delawares through the Cherokee Nation. The agency conducted a “legal review” of the situation at the Delawares’ behest. The DOI concluded the 1979 position should be retracted and published a “notice of intent” to do the same. See 61 Fed.Reg. 33,534-35 (June 27, 1996). The DOI elected not to follow the Part 83 procedures because they do not apply to “already acknowledged” tribes; and under the agency’s new position, the Delawares had been acknowledged since 1867. See 25 C.F.R. § 83.3(b). The agency issued its final decision, after notice and comment, in September 1996. See 61 Fed.Reg. 50,862-63 (Sept. 27, 1996). The final decision declared “the Delaware Tribe of Indians is a tribal entity recognized and eligible for funding and services from the Bureau of Indian Affairs by virtue of its status as an Indian Tribe.” Id. at 50,863.
On October 2, 1996, the Cherokee Nation sued the DOI. Cherokee Nation of Okla. v. Babbitt, 944 F.Supp. 974 (D.D.C.1996). The Nation alleged the agency violated the Administrative Procedure Act (“APA”), 5 U.S.C. §§ 701-706, when it extended recognition to the Delawares. The district court, upon the DOI’s motion, dismissed the suit because the Delawares were an indispensable party that could not be joined because of sovereign immunity. Cherokee Nation, 944 F.Supp. at 986. The D.C. Circuit reversed, holding the Delawares could not assert sovereign immunity because they relinquished their tribal sovereignty when they entered into an agreement with the Cherokee Nation in 1867. Cherokee Nation of Okla. v. Babbitt, 117 F.3d 1489, 1503 (D.C.Cir.1997). The D.C. Circuit, however, limited its holding to the joinder issue and remanded the case for the district court to decide the “proper interpretation of the 1867 agreement with the Delaware Tribe[ ] as a party to the proceedings and in light of the full administrative recordf.j” 1 Id. at 1503 n. 15. On remand, the district court transferred the case to the Northern District of Oklahoma because it lacked personal jurisdiction over the Delawares.
There, the district court extended “great deference” to the DOI and concluded its retraction of the 1979 letter did not violate the APA. Cherokee Nation of Okla. v. Norton, 241 F.Supp.2d 1368, 1373-74 (N.D.Okla.2002). The court reasoned the Delawares were a federally recognized tribe prior to 1979 because (1) a claims statute appropriated funds to the “Delaware Tribe of Indians,” and (2) “the Supreme Court explicitly and unambiguously declared that the Delaware Tribe of Indians was a federally recognized Indian tribe in Delaware Tribal Business Committee v. Weeks, 430 U.S. 73, 97 S.Ct. 911, 51 L.Ed.2d 173 (1977).” Id. at 1372-73. The court therefore did not consider the initial 1867 agreement entered into between the *1078Cherokee Nation and Delawares. Id. at 1372.
The Cherokee Nation appeals. We have jurisdiction, 28 U.S.C. § 1291, and “afford no particular deference to the district court’s review of [the] agency[’s] action; our review of the administrative record pertaining to the challenged action is independent.” Pennaco Energy Inc. v. United States Dep’t of the Interior, 377 F.3d 1147, 1156 (10th Cir.2004) (internal quotations and citation omitted). Because the DOI’s final decision is contrary to Supreme Court precedent and the Federally Recognized Indian Tribe List Act, we reverse.
II.
The APA requires an agency to articulate a satisfactory explanation for its action. Kansas v. United States, 249 F.3d 1213, 1228-29 (10th Cir.2001). Agency action must be upheld, if at all, on the basis the agency articulated. Federal Power Comm’n v. Texaco Inc., 417 U.S. 380, 397, 94 S.Ct. 2315, 41 L.Ed.2d 141 (1974); Pennaco Energy Inc., 377 F.3d at 1157. An agency’s action, on the other hand, may be set aside under the APA if it is arbitrary, capricious, an abuse of discretion, or contrary to law. 5 U.S.C. § 706(2)(A). “And the Act has been interpreted ... to require agencies, on pain of being found to have acted arbitrarily and capriciously, to comply with their own regulations[.]” Miami Nation of Indians of Ind., Inc. v. United States Dep’t of the Interior, 255 F.3d 342, 348 (7th Cir.2001); Utahns for Better Transp. v. United States Dep’t of Transp., 305 F.3d 1152, 1165 (10th Cir.2002). Furthermore, although the APA’s arbitrary and capricious standard is ordinarily a deferential one, see id, at 1164, such deference is not unfettered nor always due. See General Dynamics Land Sys. Inc. v. Cline, 540 U.S. 581,-, 124 S.Ct. 1236, 1248, 157 L.Ed.2d 1094 (2004) (explaining no deference is owed to a clearly wrong agency interpretation); Adams Fruit Co., Inc. v. Barrett, 494 U.S. 638, 649-50, 110 S.Ct. 1384, 108 L.Ed.2d 585 (1990) superceded by 29 U.S.C. § 1854 (explaining a precondition to agency deference is a congressional delegation of administrative authority); Watt v. Alaska, 451 U.S. 259, 273, 101 S.Ct. 1673, 68 L.Ed.2d 80 (1981) (explaining an agency interpretation that conflicts with an earlier interpretation is entitled to considerably less deference than a consistently held position).
In this case, the DOI based its final decision on a “legal analysis of the pertinent treaties and agreements as well as a review of [its] administrative practice.” 61 Fed.Reg. at 50,863. More specifically, the agency’s recognition of the Delawares was based solely on its analysis of the treaties and agreements entered into by the Cherokee Nation and Delawares in the 1860s. The DOI’s “review” of its administrative practice over the next century was simply to confirm the Delawares’ status. The DOI does not maintain its administrative practice from 1867 to 1979 “reconstituted” or “restored” the Delawares as a tribe.2 The resolution of this *1079case thus turns on the status of the Delawares under the treaties and the agreements entered into by the Cherokees and Delawares in the 1860s. We do not afford any deference to the DOI’s position on this issue because Congress did not give it the discretion to administer those treaties and agreements. Adams Fruit Co., 494 U.S. at 649, 110 S.Ct. 1384; Citizen Band of Potawatomi Indian Tribe of Okla. v. Collier, 142 F.3d 1325, 1332 (10th Cir.1998); see also Cherokee Nation, 117 F.3d at 1499. We now turn to those treaties and agreements.
III.
The history of the Delawares’ tortured migration westward has been told elsewhere, see Weeks, 430 U.S. at 75-79 & n. 2, 97 S.Ct. 911, and we need not repeat it. Suffice it to say, the “main body” of Delawares resided on a reservation in Kansas in the 1850s. Id. at 77, 97 S.Ct. 911. Notwithstanding promises to the contrary, see id., the United States sought to move the Delawares again in 1866. To that end, the United States entered into a treaty with the Delawares. Treaty with the Delawares, July 4, 1866, U.S.-Del. Indians, 14 Stat. 793 (“1866 Delaware Treaty”). The 1866 Delaware Treaty provided, among other things, the Delawares could purchase from the United States “a tract of land ceded to the Government by the Choctaws and Chickasaws, the Creeks, or the Seminóles, or which may be ceded by the Cherokees in the Indian country [now Oklahoma], to be selected by the Delawares in one body in as compact form as practicable^]”
The United States subsequently entered into a treaty with the Cherokee Nation. Treaty with the Cherokee, July 19, 1866, U.S.-Cherokee Nation, 14 Stat. 799 (“1866 Cherokee Treaty”). Article 15 of the 1866 Cherokee Treaty provided an “incorporation option” and “preservation option” for friendly Indians settling upon Cherokee lands:
The United States may settle any civilized Indians, friendly with the Cherokees and adjacent tribes, within the Cherokee country, on unoccupied lands east of 96, on such terms as may be agreed upon by any such tribe and the Cherokees, subject to the approval of the President of the United States, which shall be consistent with the following provisions, viz:
[Incorporatian Option ] Should any such tribe or band of Indians settling in said country abandon their tribal organization, there being first paid into the Cherokee national fund a sum of money which shall sustain the same proportion to the then existing national fund that the number of Indians sustain to the whole number of Cherokees then residing in the Cherokee country, they shall be incorporated into and ever after remain a part of the Cherokee Nation, on equal terms in every respect with native citizens.
[Preservation Option ] And should any such tribe, thus settling in said country, decide to preserve their tribal organizations, and to maintain their tribal laws, customs, and usages, not inconsistent with the constitution and laws of the Cherokee Nation, they shall have a district of country set off for their use by *1080metes and bounds equal to one hundred and sixty acres, if they should so decide, for each man, woman, and child of said tribe, and
[1] shall pay for the same into the national fund such price as may be agreed on by them and the Cherokee Nation, subject to the approval of the President of the United States....
[2] And the said tribe thus settled shall also pay into the national fund a sum of money, to be agreed on by the respective parties, not greater in proportion to the whole existing national fund and the probable proceeds of the lands herein ceded or authorized to be ceded or sold than their numbers bear to the whole number of Cherokees then residing in said country, and thence afterwards they shall enjoy all the rights of native Cherokees.
(emphasis added).
On April 8, 1867, the Cherokee Nation entered into “Articles of Agreement” with the Delawares (“1867 Agreement”) pursuant to Article 15 of the 1866 Cherokee Treaty. The preamble to the 1867 Agreement provides the Cherokee Nation and Delawares held a “full and free conference ... looking to a location of the Delawares upon the Cherokee lands, and their consolidation with said Cherokee Nation[.]” (emphasis added). The agreement provided for both conditions.
The Cherokee Nation first “agreefd] to sell to the Delawares, for their occupancy, a quantity of land east of the line of the 96 west longitude, in the aggregate equal to 160 acres of land for each [registered] individual of the Delaware Tribe ... [with] the selections of the lands to be purchased ... made by said Delawares in any part of the Cherokee reservation east of said line of 96[.]”3 (emphasis added). The Delawares paid $157,600 (one dollar per acre) for such occupancy rights and a preferred allotment position. The “Delawares further agreefd], that there shall be paid ... a sum of money, which shall sustain the same proportion to the existing Cherokee National fund, that the number of Delawares registered as above mentioned, and removing to the Indian country, sustains to the whole number of Cherokees residing in the Cherokee Nation.” The Delawares paid $121,824.28 into the Cherokee national fund based on the formula recited in the agreement. The 1867 Agreement concluded:
On fulfillment by the Delawares of the foregoing stipulations, all the members of the tribe, registered as above provided, shall become members of the Cherokee Nation, with the same rights and immunities, and the same participation (and no other,) in the national funds, as native Cherokees, save as hereinbefore provided. And the children hereafter born of smh Delawares so incorporated *1081into the Cherokee Nation, shall in all respects be regarded as native Cherokee a
(emphasis added).
The 1867 Agreement was “subject to the approval of the President of the United States[.]” The Secretary of the DOI, then Orville H. Browning, transmitted the agreement to the President Secretary Browning’s transmittal letter explained the agreement “providfed] for uniting the two tribes, as contemplated by the Cherokee Treaty of July 19th 1866” and “recommend[ed] that it be approved.” (emphasis added). President Andrew Johnson approved the agreement. The registered Delawares fulfilled all of the stipulations in the 1867 Agreement and moved onto selected 160-acre tracts scattered throughout the Nation.
IV.
The genesis of the present case is the DOI’s 1996 decision to extend Federal recognition to the Delawares based on its legal analysis of the 1866 Cherokee Treaty and 1867 Agreement. The agency concluded the agreement evidenced the Delawares’ election of the treaty’s “preservation option” because it required two payments (whereas the incorporation option only required one) and Delawares made two payments ($157,600 and $121,824) to the Cherokee Nation. The DOI therefore maintains the Delawares preserved their tribal identity when they moved to the Cherokee Nation in the 1860s.
We do not begin with a clean slate. In fact, every court to consider the actual terms of the 1866 Cherokee Treaty and 1867 Agreement has explicitly or implicitly rejected the DOFs reading of the agreement. See Jou0rneycake v. Cherokee Nation, 28 Ct.Cl. 281, 311 (1893) affd as modified 155 U.S. 196, 15 S.Ct. 55, 39 L.Ed. 120 (1894) (holding that under the 1867 Agreement “two independent bodies politic united and became one, the lesser, according to its terms, being merged into the greater.”); Cherokee Nation v. Journeycake, 155 U.S. 196, 210-11, 15 S.Ct. 55, 39 L.Ed. 120 (1894) (holding that under the 1867 Agreement the “Delawares became incorporated into the Cherokee Nation, and are members and citizens thereof!.]”); Delaware Indians v. Cherokee Nation, 38 Ct.Cl. 234, 256 (1903) aff'd 193 U.S. 127, 24 S.Ct. 342, 48 L.Ed. 646 (1904) (holding that “[b]y the introduction and admission of the Delawares as part of the Cherokee Nation they became a part of the people of such nation and bound in common with the Cherokees by the political power of the nation].]”); Delaware Indians v. Cherokee Nation, 193 U.S. 127, 135, 24 S.Ct. 342, 48 L.Ed. 646 (1904) (reaffirming the purpose of the 1867 Agreement was “to incorporate the registered Delawares into the Cherokee Nation, with full participation in the political and property rights of citizens of that nation.”); Cherokee Nation, 944 F.Supp. at 982 rev’d on other grounds 117 F.3d 1489 (D.C.Cir.1997) (holding the “Delawarefs] settled in Cherokee Nation territory pursuant to the first provision of Article 15, under which the settling Delaware became full and equal Cherokee Nation citizens.”); Cherokee Nation, 117 F.3d at 1503 (holding that “by entering into the 1867 Agreement the Delaware Tribe of Indians relinquished its tribal identity or sovereignty in relation to the Cherokee Nation.”). We now join them.
A.
In Journeycake, 155 U.S. at 196, 15 S.Ct. 55, the Supreme Court considered a dispute between the Delawares and Cherokee Nation over the proper distribution of national funds. The Cherokee National *1082Council had directed certain rent proceeds be distributed to “native Cherokees,” to the exclusion of Delawares. The Delawares filed suit in the court of claims, alleging the Cherokee Nation’s discriminatory distribution of the rental proceeds violated the 1867 Agreement.4 The case therefore “hingefd] on the status of the individual Delawares as members and citizens of the Cherokee Nation, and the rights secured to them by the agreement of April 8, 1867.” Id. at 204, 15 S.Ct. 55.
The Court, after reviewing the 1866 Cherokee Treaty and 1867 Agreement, easily concluded that because “the registered Delawares have become incorporated into the Cherokee Nation, and are members and citizens thereof, it follows necessarily that they are, equally with the native Cherokees, the owners of, and entitled to share in the profits and proceeds of, [the leased] lands.” Id. at 210-11, 15 S.Ct. 55. The Court rejected the Cherokee Nation’s arguments to the contrary based on the “plain import of the language used in the [1867] agreement^]” Id. at 216, 15 S.Ct. 55. The agreement’s language compelled the Court to “conclude that by such agreement the Delawares became incorporated into the Cherokee Nation, became members thereof, and, as such, entitled equally with the native Cherokees to all then' rights in the reservation and [leased lands].” Id,
In so holding, the Court considered evidence of the Delawares’ two payments to the Cherokee Nation, id. at 203, 15 S.Ct. 55, and specifically analyzed the Delawares’ purchase of land occupancy rights. Id, at 212-15, 15 S.Ct. 55. The Court nevertheless found the 1867 Agreement expressed the parties’ intent to incorporate the Delawares for two reasons. First, the parties did not provide for the “setting apart of a distinct body of land in any portion of the reservation for the Delaware tribef.]” Id. at 205, 15 S.Ct. 55. The Court explained the Delawares’ failure to purchase a “distinct body of lands” was inconsistent with the settlement of “tribes as tribes within the limits of the Cherokee Nation.” Id. at 213, 15 S.Ct. 55 (emphasis added). Second, the Delawares did not purchase their lands in fee simple, see id, at 212, 214-15, 15 S.Ct. 55, but instead acquired occupancy rights in kind with all Cherokees and a preferential allotment position. Id at 213, 15 S.Ct. 55. “All this was in the line of the expressed thought of a consolidation of the[ ] Delawares with, and absorption of them into, the Cherokee Nation as individual members thereof.” Id,
Subsequently, in Delaware Indians, 193 U.S. at 127, 24 S.Ct. 342, “the Delaware Indians residing in the Cherokee Nation, as a tribe and individually, ... su[ed] ... for the purpose of determining the right of
*1083the Delaware Indians in and to the lands and funds of [the Cherokee] nation under the contract and agreement ... dated April 8, 1867.”: Id. at 129, 24 S.Ct. 342 (emphasis added) (internal quotation and citations omitted); see also Act of June 28, 1898, Chap. 517, § 25, 30 Stat. 495, at 504. The Court first rejected the Delawares’ claim that the 1867 Agreement secured to them, as a tribe, their selected lands east of the 96 meridian. Delaware Indians, 193 U.S. at 134-35, 24 S.Ct. 342. The Delawares’ argument failed because it was contrary to the Court’s holding in Jour-neycake and inconsistent with their purchase of occupancy rights, which were “conferred not upon the Delaware Nation, but upon certain registered Delawares who [were] incorporated into the Cherokee Nation.” Id. at 135, 24 S.Ct. 342 (emphasis added).
The Court also rejected the Delawares’ argument that they individually owned their selected tracts in fee simple. The Court explained the adult Delawares had only purchased occupancy rights in the Cherokee lands under the 1867 Agreement. Furthermore, the agreement provided “ ‘the children hereafter born of such Delawares so incorporated into the Cherokee Nation shall, in all respects, be regarded as native Cherokees.’ ” Id. at 138, 24 S.Ct. 342. The Court found
[t]his provision is utterly inconsistent with the grant of an estate in the lands to survive the ‘occupancy’ of the registered Delawares, Such children are to have the rights of native Cherokees, and no more. Their parents were incorporated into the Cherokee Nation with certain specific rights; the children were to stand upon an equality with their adopted brethren of the Cherokee blood.
Id. (emphasis added). The Court accordingly held the Delawares only obtained life estates in their lands selected under the 1867 Agreement. Id. at 143, 24 S.Ct. 342.
The Delawares nevertheless insisted the 1867 Agreement “should not be literally enforced in view of the understanding of the parties[ ]” and sought to introduce par-ol evidence. Id. at 140, 24 S.Ct. 342. The Court, however, found the contract unambiguous and rejected the Delawares’ resort to parol evidence. Id. at 140-42, 24 S.Ct. 342. The Court explained “no room” existed in the case to “departf ] from the familiar rules of law protecting written agreements from the uncertainties of parol testimony.” Id. at 141, 24 S.Ct. 342. “In light of the circumstances and the language used in the writing, its construction [was] not rendered difficult because of latent ambiguities.” Id. The Delawares were therefore entitled to their occupancy and preferential allotment rights, but “[i]n all other respects the Cherokee citizens, whether of Delaware or Cherokee blood, should be given equal rights in the lands and funds of the Cherokee Nation.” Id. at 146, 24 S.Ct. 342 (emphasis added).5
B.
Based on the foregoing, the DOI’s conclusion the Delawares preserved their tribal identity under the 1866 Cherokee Trea*1084ty and 1867 Agreement is clearly contrary to Supreme Court precedent. The “rights adjudicated” in Joumeycake and Delaware Indians “turned upon the construction of the agreement of April 8, 1867, and its nature and the history of the events which led up to its execution[.]” Delaware Indians, 193 U.S. at 134, 24 S.Ct. 342. The Court held the unambiguous language of the 1867 Agreement provided for the Delawares’ incorporation into the Cherokee Nation with their children taking only the same rights as other citizens. Id. at 143, 24 S.Ct. 342; Journeycake, 155 U.S. at 216, 15 S.Ct. 55. We are “bound by the Supreme Court’s interpretation of that Agreement in Journeycake and Delaware Indians.” Cherokee Nation, 117 F.3d at 1500; see also State Oil Co. v. Khan, 522 U.S. 3, 20, 118 S.Ct. 275, 139 L.Ed.2d 199 (1997). “An agency also must conform its conduct to a decision of the Supreme Court in all future cases, even if the agency believes that the Court was wrong.” 1 Richard J. Pierce, Jr., Administrative Law Treatise § 2.9, at 129 (2002) (emphasis added).
Our task is therefore simple. Although we seek to avoid engaging in a repetitive analysis of the 1866 Cherokee Treaty and 1867 Agreement—an analysis the Supreme Court has twice engaged in—we again explain why the Delawares did not preserve their tribal identity under those documents. The 1866 Cherokee Treaty provided for the settlement of Indians within the Cherokee Nation. The terms the tribes agreed upon for such settlement, however, had to be “consistent” with one of the options provided in Article 15 of the 1866 Cherokee Treaty. The unambiguous language of the 1867 Agreement, including the provisions for the Delawares’ two payments, is consistent with the Delawares’ selection of the incorporation option of Article 15. Specifically, the Delawares made a proportional payment of $121,824 into the national fund and provided they were consolidating with and incorporating into the Cherokee Nation. That the Delawares made an additional payment of $157,600 for land occupancy and preferential allotment rights is not inconsistent with the incorporation option. In contrast, and for the reasons detailed below, the language of the agreement and the nature of its execution are inconsistent with Article 15⅛ preservation option.
To begin, the 1867 Agreement describes the Delawares consolidation with or incorporation into the Cherokee Nation three times. We agree with the Supreme Court (as we must) and the D.C. Circuit that the agreement’s language is unambiguous. Delaware Indians, 193 U.S. at 141, 24 S.Ct. 342; Cherokee Nation, 117 F.3d at 1501. “Consolidation” and “incorporation” carried the same meanings in 1867 as they do today: to unite. Compare Webster’s Dictionary of the English Language 279 (consolidate), 677 (incorporate) (1864) with Webster’s Third New International Dictionary 484 (consolidate), 1145 (incorporate) (1981). The DOI nevertheless concluded “the Agreement uses the language ‘consolidation’ in the context of the physical location of the Delaware from Kansas to Cherokee country, not in the context of governmental purposes.” The agency’s reading is, however, inconsistent with the plain language of the 1867 Agreement, which provides the parties were “looking to a location of the Delawares upon the Cherokee lands, and their consolidation with said Cherokee Nation[.]” (emphasis added). With respect to “incorporation,” the DOI suggests the language can be read consistent with Article la’s preservation option. Perhaps. The problem is the Supreme Court specifically rejected the DOI’s reading in Delaware Indians. There, the Court explained the “Delawares were made part of the Chero*1085kee Nation ” and became “a component part ” of the nation “on equal terms with other citizens.” Delaware Indians, 193 U.S. at 144, 24 S.Ct. 342 (emphasis added). Furthermore, the agreement provides Delaware children shall be regarded as ua-live Cherokees. Such a provision is wholly inconsistent with the “preservation” of tribal identity. See Cherokee Nation, 117 F.3d at 1502.
Next, as the Supreme Court explained, the 1867 Agreement is important for what it does not contain. Article 15⅛ preservation option contains the mandatory condition that tribes settling under it “shall have a district of country set off for their use by metes and bounds[.]” (emphasis added). In Journeycake, 155 U.S. at 205, 213, 15 S.Ct. 55, the Court twice mentioned the agreement’s crucial omission of a “provision for the setting apart of a distinct body of lands” to support its holding the Delawares “became incorporated into the Cherokee Nation[.]” Id. at 216, 15 S.Ct. 55.
In this appeal, the Delawares (and to a lesser extent the DOI) advance the novel theory they actually selected and settled upon a ten-by-thirty mile tract of land in the Cherokee Nation. Absolutely nothing in the administrative record supports the Delawares’ theory. See supra, n. 3. Instead, the 1867 Agreement “eontem-plate[d] personal selection of separate tracts by individual Delawares.” Journeycake, 155 U.S. at 205, 15 S.Ct. 55. The agreement’s language could not be more clear: “the selections of the lands to be purchased by the Delawares, may be made by said Delawares in any part of the Cherokee reservation east of said line of 96[.]” (emphasis added). The evidence in the administrative record demonstrates the Delawares did, in fact, select individual tracts of lands for then' homes throughout the reservation. That some, or even “most,” Delawares selected their tracts in the Cooweescoowee district of the reservation is immaterial.
Most importantly, the DOI’s theory that the Delawares’ two payments to the Cherokee Nation evidences “preservation” rather than “incorporation” is misguided. In Journeycake, 155 U.S. at 203, 15 S.Ct. 55, the Court was aware of the payments and did not express any disagreement with the finding that the Delawares’ proportional payment into the national fund was not “susceptible of misconstruction and concerning it no controversy has arisen.” Journeycake, 28 Ct.Cl. at 307. The Court then based its decision on the land purchase payment. In fact, the Court considered the Delawares’ purchase of land occupancy rights indicative of their intent to incorporate. Journeycake, 155 U.S. at 212-13, 15 S.Ct. 55. Further, the Court reaffirmed Journey cake’s holding and reasoning in Delaware Indians, 193 U.S. at 143, 24 S.Ct. 342, when it concluded the Delawares only purchased life estates in the Cherokee lands. The Delawares’ purchase of life estates in scattered tracts throughout the Cherokee Nation is inconsistent with the actions of a people seeking to “preserve” their tribal identity.
The DOI and Delawares also argue the 1867 Agreement is ambiguous and urge us to consider parol evidence. We decline for three reasons. First, the admission of parol evidence is improper because the 1867 Agreement is unambiguous. See Richardson v. Hardwick, 106 U.S. 252, 254, 1 S.Ct. 213, 27 L.Ed. 145 (1882); Eastern Band of Cherokee Indians v. United States, 117 U.S. 288, 311, 6 S.Ct. 718, 29 L.Ed. 880 (1886). Second, we cannot tell the Supreme Court that it incorrectly concluded the agreement did not suffer from any ambiguities requiring the consideration of parol evidence. Delaware Indians, 193 U.S. at 141, 24 S.Ct. 342; *1086Hutto v. Davis, 454 U.S. 370, 375, 102 S.Ct. 703, 70 L.Ed.2d 556 (1982) (per cu-riam) (explaining that “unless we wish anarchy to prevail within the federal judicial system, a precedent of [the Supreme] Court must be followed by the lower federal courts no matter how misguided the judges of those courts may think it to be.”). Third, and assuming for the moment the agreement is ambiguous (w’hich it is not) and the Supreme Court had not held it unambiguous (which it did), the Delawares would still not be in any better position. The parties’ contemporaneous actions evidenced their belief the Delawares incorporated into the Cherokee Nation.6 See Journeycake, 155 U.S. at 216-17, 15 S.Ct. 55
We finally note the DOI’s and Delawares’ reliance on Weeks is misplaced. In Weeks, 430 U.S. at 75, 97 S.Ct. 911, the Supreme Court considered whether a claims statute excluding the “Kansas Delawares”—the Delaware Indians who remained in Kansas under the 1866 Delaware Treaty—from the statutory distribution of a claims award violated the Equal Protection Clause. The Court commented that “[d]espite their association with the Cherokees, these Indians, called ‘Cherokee Delawares’ in this suit, have over the years maintained a distinct group identity, and they are today a federally recognized tribe.” Id. at 77 & n. 8, 97 S.Ct. 911. The Court’s dicta, see Cherokee Nation, 117 F.3d at 1502, indicated Congress’ distribution of a claims award to the “Delaware Tribe of Indians,” see Act of April 21, 1904, Chap. 1402, § 21, 33 Stat. 189, at 222, w’as sufficient to recognize the Delawares as a tribe for the limited purpose of the claims statute at issue in that case. Weeks, 430 U.S. at 77 n. 8, 97 S.Ct. 911; see also id. at 94, 97 S.Ct. 911 (Stevens, J., dissenting). As Cohen’s handbook on Federal Indian law explains: *1087See Felix S. Cohen, Handbook of Federal Indian Law Chap. 1, § B2d, at 12 (1982 ed.). For illustrative purposes, Cohen cites claims statutes allowing the Delawares to bring suit. Id. at 12 n. 64; see also Federal Indian Law Chap. VI, § B-l, at 463 & n. 32 (U.S. Dep’t of Interior 1958); Cherokee Nation, 117 F.3d at 1502.
*1086The question whether a group is a tribe for purposes of statutes allowing claims to be asserted against the United States has arisen many times. Where several Indian groups are generally considered a single tribe for political and administrative purposes, Congress may nevertheless assign tribal status to portions of the tribe for claims purposes. For example, Tribe A and Tribe B have combined to form Tribe C and share a common reservation and common funds. However, at some time prior to their merger, Tribe A had suffered an injury for which Congress later offers redress in the form of a jurisdictional act. In such a ease Congress may recognize Tribe A as a tribe, entitled to bring suit in the Court of Claims, even though for most other purposes it is only a part of Tribe C.
*1087At most, Weeks stands for the proposition the Delawares reconstituted for claims purposes. Whether the Delawares were reconstituted—be it through Act of Congress or administrative practice—sometime after 1867 is not before us. See mirra n. 2. The present case, instead, turns on the DOI’s interpretation of the 1866. Cherokee Treaty and 1867 Agreement. We thus have a duty to follow Journeyeake and Delaware Indians because they directly control our interpretation of the agreement. Even assuming jowmeyeake and Delaware Indians conflict with the dicta in Weeks (which they do not), we nevertheless would be bound by those decisions. See Agostini v. Felton, 521 U.S. 203, 237, 117 S.Ct. 1997, 138 L.Ed.2d 391 (1997) (explaining that “[i]f a precedent of th[e] Court has direct application in a case, yet appears to rest on reasons rejected in some other line of decisions, the Court of Appeals should follow the case which directly controls, leaving to th[e] Court the prerogative of overruling its own decisions.”); see also F.T.C. v. Kuykendall, 371 F.3d 745, 752 (10th Cir.2004) (en banc).
V.
We are not unsympathetic to the Delawares’ cause. The DOI’s unlawful actions, however, cannot provide the Delawares the status they seek. The agency’s decision to extend recognition to the Delawares rested on an alleged “comprehensive legal analysis” that devoted three sentences, in a footnote, to the Supreme Court’s decisions interpreting the 1866 Cherokee Treaty and 1867 Agreement. Agencies, like courts, must follow Supreme Court decisions and congressional acts. The DOFs recognition of the Delawares in this case was contrary to the United States Supreme Court’s decisions in Jowmeycake and Delaware Indians and violated § 103(3) of the Federally Recognized Indian Tribe List Act.
Agencies, moreover, must follow their own rales and regulations. The DOI used a procedure heretofore unknown to the law—“retract and declare”—to purportedly re-recognize the Delawares. In so doing, the DOFs actions were arbitrary and capricious. The agency simply elected not to follow the Part 83 procedures for recognizing an Indian tribe and, furthermore, did not even properly waive application of those procedures. See 25 C.F.R. § 1.2. We accordingly hold unlawful and set aside the DOFs 1996 final decision. 5 U.S.C. § 706(2)(A). Any action taken on the agency’s 1996 final decision is void. “Further comment on this case is unnecessary.” Journeycake, 155 U.S. at 218, 15 S.Ct. 55.
REVERSED.