PAUL KELLY, JR., Circuit Judge.
Plain tiff-Appellant the Osage Nation (“the Nation”) appeals from the grant of summary judgment for Defendants-Appel-lees. The Nation sought (1) a declaratory judgment that the Nation’s reservation, which comprises all of Osage County, Oklahoma, has not been disestablished and remains Indian country within the meaning of 18 U.S.C. § 1151; (2) a declaratory judgment that Nation members who are employed and reside within the reservation’s geographical boundaries are exempt from paying state income tax; and (3) injunctive relief prohibiting Defendants from collecting income tax from such tribal members. 1 Aplt.App. at 24.
The pivotal issue in this case is whether the Nation’s reservation has been disestablished, not Oklahoma’s tax policies. The district court held that the Osage reservation had been disestablished; that tribal members who work and live on non-ti*ust/ non-restricted land in Osage County are not exempt from state income tax; and that “[t]he Osage have not sought to reestablish their claimed reservation or to challenge [Oklahoma’s] taxation until recently,” and Oklahoma’s longstanding reliance counsels against now establishing Osage County as a reservation. 2 Aplt.App. at 389-407. The district court also denied the Nation’s Rule 59 motion. 2 Aplt.App. at 416. On appeal, the Nation argues that its reservation has never been disestablished and is coterminous with Osage County; that tribal members who work and live in Osage County are exempt from state income tax; and that the district court should not have applied equitable considerations to this case. Our jurisdiction arises under 28 U.S.C. § 1291, and because we agree that the Osage reservation has been disestablished, we affirm.
Background
In 1872, Congress established a reservation for the Osage Nation in present day Oklahoma. See Act of June 5, 1872, ch. 310, 17 Stat. 228 (An Act to Confirm to the Great and Little Osage Indians a Reservation in the Indian Territory). In 1887, due to increased demand for land by white settlers and a desire to assimilate tribal nations, Congress passed the Indian General Allotment Act. See Act of February 8, 1887, ch. 119, 24 Stat. 388 (codified as amended at 25 U.S.C. §§ 331-334, 339, 341-342, 348-349, 354, 381). The Osage reservation was expressly exempted from this Act. 25 U.S.C. § 339. In 1907, Oklahoma became a state, and the Osage reservation was incorporated into the new state as Osage County as provided for in the Oklahoma Enabling Act. See Act of June 16, 1906, ch. 3335, 34 Stat. 267, §§ 2, 21; see also Okla. Const., art. XVII, § 8 (“The Osage Indian Reservation with its present boundaries is hereby constituted one county to be know as Osage County.”). Osage County, the largest county in Oklahoma, covers about 2,250 square miles (about 3% of Oklahoma’s total land area).
Contemporaneous to passing the Oklahoma Enabling Act, Congress enacted the Osage Allotment Act.
See
Act of June 28, 1906, ch. 3572, 34 Stat. 539. The 1906 Osage Allotment Act severed the mineral estate from the surface estate of the reservation and placed it in trust for the tribe.
Id.
at §§ 2-3. The Act included several provisions regarding tribal government and tribal membership and granted the Osage tribal council general tribal authority.
See Logan v. Andrus,
In 2004, Congress passed a statute clarifying the 1906 Act and authorizing the Osage Nation to determine its membership and government structure. Pub.L. No. 108-431, 118 Stat. 2609 (2004) (An Act to Reaffirm the Inherent Sovereign Rights of the Osage Tribe to Determine Its Membership and Form of Government). This Act refers to the Osage as “based in Pa-whuska, Oklahoma,” id. at § 1, but does not specifically refer to an Osage reservation in the text of the statute, and does not address the reservation status of Osage land.
In 1999, a tribal member who was employed by the Tribe on trust land and lived within the boundaries of the Osage County on fee land protested the State’s assessment of income tax on her.
Osage Nation v. Oklahoma ex rel. Okla. Tax Comm’n,
The state of Oklahoma and the Oklahoma Tax Commission filed a motion to dismiss, arguing that the Nation’s suit was barred by the Eleventh Amendment.
Osage Nation,
On remand, the remaining defendants moved to dismiss, and the district court converted their motion to one for summary judgment. 1 Aplt.App. at 204. The district court determined that “the Osage reservation ceased to exist more than a century ago,” 2 Aplt.App. at 389, and that tribal members that work and live on private fee lands in Osage County are not exempt from state income tax, 2 Aplt.App. at 397-02. Applying
City of Sherrill v. Oneida Indian Nation,
Discussion
It is well established that Congress has the power to diminish or dises
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tablish a reservation unilaterally, although this will not be lightly inferred.
See, e.g., Solem v. Bartlett,
We have noted that “the Supreme Court has applied, without comment, a
de novo
standard of i-eview in determining congressional intent [regarding reservation boundary diminishment].”
Yazzie,
We apply the three-part test summarized in
Solem,
to determine whether a reservation has been diminished or disestablished. Congress’s intent at the time of the relevant statute governs our analysis. The Supreme Court has repeatedly stated and Defendants have conceded that allotment/opening of a reservation alone does not diminish or terminate a reservation. Aplee. Br. at 18. In ascertaining Congress’s intent, the effect of an allotment act depends on both the language of the act and the circumstances underlying its passage.
Solem,
With these standards in mind, we turn to whether the 1906 Osage Allotment Act disestablished the Osage reservation.
A. Statutory Language
Statutory language is the most probative evidence of congressional intent
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to disestablish or diminish a reservation. “Explicit reference to cession or other language evidencing the present and total surrender of all tribal interests strongly suggests that Congress meant to divest from the reservation all unallotted opened lands.”
Solem,
The manner in which a statute compensates a tribe for opened land is also instructive. Some statutes provide that the tribe will be paid a sum-certain amount as compensation for all of the unallotted land. Others provide payment to the tribe as the lands are sold. Sum-certain payments indicate an intent to terminate the reservation, but payment that is contingent on future sales usually indicates an intent not to terminate.
Compare DeCoteau,
The
Solem
court found additional factors weighing in favor of continued reservation status: (a) authorization for the Secretary of the Interior to set aside lands for tribal purposes; (b) permission for tribal members to obtain individual allotments before the land was officially opened to non-Indian settlers; and (c) reservation of the mineral resources for the tribe as a whole.
B. Circumstances Surrounding Passage of the Act
If the statute is ambiguous, we turn to the circumstances surrounding the passage of the act, in particular the manner in which the transaction was negotiated and its legislative history, for evidence of a contemporaneous understanding that the affected reservation would be diminished or disestablished as a result of the proposed legislation.
Solent,
The manner in which the Osage Allotment Act was negotiated reflects clear congressional intent and Osage understanding that the reservation would be disestablished. The Act was passed at a time where the United States sought dissolution of Indian reservations, specifically the Oklahoma tribes’ reservations.
See
Francis Paul Prueha, The Great Father 737-57 (1984) (Aplee.Supp.Add.104-24). In preparation for Oklahoma’s statehood, the Dawes Commission had already implemented an allotment process with the Five Civilized Tribes that extinguished national and tribal title to lands within the territory and disestablished the Creek and other Oklahoma reservations.
See
H.R.Rep. No. 59-496, at 9, 11 (1906) (Aplee. Supp.
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The Osage themselves presented an allotment act to Congress in February 1906, and by June of that year, Congress passed the Osage Allotment Act. Baird at 70 (2 ApltApp. at 238). A primary concern during the negotiations was a desire to ensure that some tribal members were not unfairly enriched at the expense of other tribal members. These concerns were addressed by allotting land in several rounds, severing the mineral estate and placing it in trust for the tribe, and providing for a form of tribal government.
See, e.g.,
1 Division Hearings, at 11-14, 55-56 (Aplt.
The legislative history and the negotiation process make clear that all the parties at the table understood that the Osage reservation would be disestablished by the Osage Allotment Act, and uncontested facts in the record provide further evidence of a contemporaneous understanding that the reservation had been dissolved. Historian Lawrence Kelly concludes that “[tjreatises and articles in professional journals that have considered the history of the former Osage Reservation have acknowledged that, after the Osage Allotment Act and Oklahoma’s admission to the Union in accordance with the Oklahoma Enabling Act, the Osage Reservation no longer existed and that area became Osage County, a subdivision of the State of Oklahoma.” Kelly Aff., ¶ 10 (2 ApltApp. 244). Historian Francis Prucha has thoroughly discussed the United States’ persistent efforts to end tribal control in the Indian Territory, which eventually became part of Oklahoma. Pincha at 738-57 (Aplee. Supp.
Instead of presenting evidence regarding widely held understanding of the Osage Allotment Act at the time it was passed, the Osage Nation primarily presents evidence of continued existence of their reservation contemporaneous to this litigation including: (1) the legislative history of the 2004 Osage Act, which refers to the Osage as a “federally recognized tribe with a nearly 1.5 million-acre reservation in northeast Oklahoma,” H.R.Rep. No. 108-502, at 1 (2004); (2) the Assistant Secretary for Indian Affairs’ certification of an Osage Tribe Liquor Control Ordinance in 2005, Aplt.
C. Post-enactment History
The final factor used to determine Congressional intent to disestablish is subsequent events. Actions by Congress, the Bureau of Indian Affairs (BIA), and local authorities with regard to the unallotted open lands, “particularly in the years immediately following the opening, ha[ve] some evidentiary value.”
Solem,
The uncontested facts support disestablishment under this prong of the
Solem
test. After enactment, federal officials responsible for the Osage lands repeatedly referred to the area as a “former reservation” under state jurisdiction. For example, an annual report from the Superintendent to the Commissioner of Indian Affairs notes that his office “has experienced no difficulty maintaining order.... This duty, of course, falls to the County and State Officials.” 2 Aplt.App. at 259 (1916 report);
see also
2 Aplt.App. at 263 (1919 report) (same); 2 Aplt.App. at 268 (1920 report) (“Osage County, formerly Osage Indian Reservation, is organized under the constitution of the State of Oklahoma and the duty of maintaining order and enfore-
*1127
ing the law is primarily in the hands of the County officials.”); 2 Aplt.App. at 272 (1921 report) (same); 2 Aplt.App. at 276 (1922 report) (same). Such “ ‘jurisdictional history’ ... demonstrates a practical acknowledgment that the Reservation was diminished.”
Hagen,
In addition, uncontested population demographics demonstrate a dramatic shift in the population of Osage County immediately following the passage of the Osage Allotment Act. From the 1907 Special Census following the founding of Oklahoma to the 1910 Census, Osage County’s population grew by a third. Glimpse Aff., ¶ 9 (2 Aplt.App. at 307-08); 2 Aplt.App. at 319-29 (census data for 1907, 1910, 1920, and 1930). By 1910, Osage Indians represented roughly six percent of the Osage County population. Glimpse Aff., 119 (2 Aplt. App. at 307-08). From 1910 to 1920, the county’s population grew by 82%, but the Indian population in the county (not limited to Osage Indians) dropped to roughly 3 percent. Glimpse Aff., ¶ 10 (2 Aplt.App. at 308). As of the 2000 Census, Osage County was 84% non-Indian, Osage Indians accounting for 3.5% of the county’s population. Glimpse Aff., f 14 (2 ApltApp. al 309); 2 Aplt.App. at 331 (2000 population demographics map for Osage County).
Land ownership also dramatically shifted from tribal members to nonmembers through certificates of competency. By 1957, 1.1 million of the 1.4 million-acre county was alienated from trust/restricted status, Bail’d at 83 (2 Aplt.App. at 239), and as of 1972, just 231,070 acres remained in restricted ownership. 1 Aplt.App. at 89. As of 2008, the United States holds about 0.04% of the total land in Osage County in trust for the Osage Nation. Harwell Aff., ¶¶ 3-6 (2 ApltApp. at 291-92). Like in
Hagen,
we think “[t]his ‘jurisdictional history,’ as well as the current population situation in [Osage County], demonstrates a practical acknowledgment that the Reservation was diminished.”
Hagen,
We conclude that the Osage reservation has been disestablished by Congress.
1
As a result, we need not reach whether tribal members who reside and earn income on fee lands located within the geographic boundaries of a reservation are exempt from state income tax. We also need not address the district court’s application of laches to this case, although we note that the Nation concedes that Oklahoma has had a “long-standing practice of asserting jurisdiction” in Osage County. 2 Aplt.App. at
356.
“[T]he longstanding assumption of
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jurisdiction by the State over an area that is [predominantly] non-Indian, both in population and in land use, may create justifiable expectations” that “merit heavy weight.”
City of Sherrill,
AFFIRMED.
The motion to withdraw as attorney filed by Kathryn L. Bass is GRANTED.
Notes
. In reaching this conclusion, we have also carefully considered the other arguments raised by the Nation including: (I) that tribal, federal, and state sovereign authorities currently co-exist within the reservation’s boundaries, Aplt. Br. at 19, 33-34; (2) that the district court improperly relied on judicial statements involving other tribes and reservations in Oklahoma, Aplt. Br. at 24; (3) that the district court improperly relied on "modern academic commentary of historians and demographers, post hoc commentary which has little probative value” and "is not subject to the legal standards applied by the Supreme Court,” Aplt. Reply Br. at 11-12, Aplt. Br. at 24; (4) that the district court placed undue reliance on modern-day demographics, Aplt. Br. at 41-42; and (5) that the Defendants' 2000 census data is misleading and underre-presents the Osage, Aplt. Reply Br. at 16-17. To the extent these arguments are not subsumed by our analysis, we are not persuaded.
