Me. Justice Brennan
delivered the opinion of the Court.
The appellants, husband and wife, are Indians. They were convicted in the Superior Court of the State of Washington of the offenses of hunting and possession of deer during closed season in violation of Wash. Rev. Code §§77.16.020 and 77.16.030 (1974). The offenses occurred on September 11, 1971, in Ferry County on un-allotted non-Indian land in what was once the north half of the Colville Indian Reservation. The Colville Confederated Tribes ceded to the United States that northern half under a congressionally ratified and adopted Agreement, dated May 9, 1891. Article 6 of that ratified Agreement provided expressly that “the right to hunt and fish in common with all other persons on lands not allotted to said Indians shall not be taken away or in anywise abridged.” Appellants’ defense was that congressional approval of Art. 6 excluded from the cession and retained and preserved for the Confederated Tribes the exclusive, absolute, and unrestricted rights to hunt and fish that had been part of the Indians’ larger rights in the ceded portion of the reservation, thus limiting governmental regulation of the rights to federal regulation and precluding application to them of Wash. Rev. Code §§ 77.16.020 and 77.16.030. The Supreme Court of Washington'held that the Superior Court had properly-rejected this defense and affirmed the convictions, 82 Wash. 2d 440, 511 P. 2d 1351 (1973). We noted probable jurisdiction, 417 U. S. 966 (1974). We reverse.
I
President Grant established the original Colville Indian Reservation by Executive Order of July 2, 1872. Washington became a State in 1889, 26 Stat. 1552, and the next year, by the Act of Aug. 19, 1890, 26 Stat. 355, Congress created the Commission that negotiated the 1891 Agreement-. By its terms, the Tribes ceded the northern half of the reservation in return for benefits which included the stipulations of Art. 6 and the promise of the United States to pay $1,500,000 in five installments. The Agreement was to become effective, however, only “from and after its approval by Congress.” Congressional approval was given in a series of statutes. The first statute was the Act of July 1, 1892, 27 Stat. 62, which “vacated and restored [the tract] to the public domain . . . ,” and “open[ed] . . . [it] to settlement . . . .” The second statute came 14 years later, the Act of June 21,1906,34 Stat. 325,377-378. That statute in terms “carr[ied] into effect the agreement,” and authorized the appropriation of the $1,500,000. Payment of the $1,500,000 was effected by five subsequent enactments from 1907 to 1911, each of which appropriated $300,000 and recited in substantially identical language that it was part payment “to the Indians on the Colville Reservation, Washington, for the cession of land opened to settlement by the Act of July first, eighteen hundred and ninety-two . . . being a part of the full sum set aside and held in the Treasury of the United States in payment for said land under the terms of the Act of June twenty-first, nineteen hundred and six, ratifying the agreement ceding said land to the United States under date of May ninth, eighteen hundred and ninety-one . . . .” (Emphasis supplied.) 34 Stat. 1015, 1050-1051 (1907); 35 Stat. 70, 96 (1908); 35 Stat. 781, 813 (1909); 36 Stat. 269, 286 (1910); 36 Stat. 1058, 1075 (1911).
The canon of construction applied over a century and a half by this Court is that the wording of treaties and statutes ratifying agreements with the Indians is not to be construed to their prejudice. Worcester v. Georgia, 6 Pet. 515 (1832). See also The Kansas Indians, 5 Wall. 737, 760 (1867); United States v. Kagama, 118 U. S. 375 (1886); Choctaw Nation v. United States, 119 U. S. 1, 28 (1886); United States v. Winans, 198 U. S. 371, 380-381 (1905); Choate v. Trapp, 224 U. S. 665, 675 (1912) ; Menominee Tribe v. United States, 391 U. S. 404, 406 n. 2 (1968). In Choate v. Trapp, supra, also a case involving a ratifying statute, the Court stated: “The construction, instead of being strict, is liberal; doubtful expressions, instead of being resolved in fayor of the United States, are to be resolved in favor of a weak and defenseless people, who are wards of the nation, and dependent wholly upon its protection and good faith.” 224 U. S., at 675. See also Seminole Nation v. United States, 316 U. S. 286, 296 (1942); Morton v. Ruiz, 415 U. S. 199, 236 (1974). Thus, even if there were doubt, and there is none, that the words “[t]o carry into effect the [1891] agreement,” in the 1906 Act, and the words “ratifying the [1891] agreement,” in the 1907-1911 laws, ratified Art. 6, application of this canon would require that we construe the series of statutes as having ratified that article.
II
Although admitted to statehood two years earlier, the State of Washington was not a party to the 1891 Agreement. The opinion of the State Supreme Court relies upon that fact to attempt a distinction for purposes of the Supremacy Clause between the binding result upon the State of ratification of a contract by treaty effected by concurrence of two-thirds of the Senate, Art. II, § 2, cl. 2, and the binding result of ratification of a contract effected by legislation passed by the House and the Senate. The opinion states that “ [o] nee ratified, a treaty becomes the supreme law of the land” (emphasis supplied), but that the ratified 1891 Agreement was a mere contract enforceable “only against those party to it,” and “not a treaty . . . [and] not the supreme law of the land.” 82 Wash. 2d, at 444, 451, 511 P. 2d, at 1354, 1358. The grounds of this attempted distinction do not clearly emerge from the opinion. The opinion states, however: “The statutes enacted by Congress in implementation of this [1891] agreement . . . are the supreme law if they are within the power of the Congress to enact . . . .” Id., at 451, 511 P. 2d, at 1358. In the context of the discussion in the opinion we take this to mean that the Congress is not constitutionally empowered to inhibit a State’s exercise of its police power by legislation ratifying a contract between the Executive Branch and an Indian tribe to which the State is not a party. The fallacy in that proposition is that a legislated ratification of an agreement between the Executive Branch and an Indian tribe is a “[Law] of the United States . . . made in Pursuance” of the Constitution and, therefore, like “all Treaties made,” is made binding upon affected States by the Supremacy Clause.
The opinion seems to find support for the attempted distinction in the fact that, in 1891, the Executive Branch was not authorized to contract by treaty with Indian tribes as sovereign and independent nations. Id., at 444,511 P. 2d, at 1354. Twenty years earlier, in 1871, 16 Stat. 544, 566, Congress had forbidden thereafter recognition of Indian nations and tribes as sovereign independent nations, and thus had abrogated the contract-by-treaty method of dealing with Indian tribes. The Act of 1871 resulted from the opposition of the House of Representatives to its practical exclusion from any policy role in Indian affairs. For nearly a century the Executive Branch made treaty arrangements with the Indians “by and with the Advice and Consent of the Senate/' Art. II, § 2, cl. 2. Although the House appropriated money to carry out these treaties, it had no voice in the development of substantive Indian policy reflected in them. House resentment first resulted in legislation in 1867 repealing “all laws allowing the President, the Secretary of the Interior, or the commissioner of Indian affairs to enter into treaties with any Indian tribes/’ Act of Mar. 29, 1867, 15 Stat. 7, 9, but this was repealed a few months later, Act of July 20, 1867,15 Stat. 18. After further unsuccessful House attempts to enter the field of federal Indian policy, the House refused to grant funds to carry out new treaties. United States Department of the Interior, Federal Indian Law 211 (1958). Finally, the Senate capitulated and joined the House in passage of the 1871 Act as a rider to the Indian Appropriation Act of 1871. Federal Indian Law, supra, at 138.
This meant no more, however, than that after 1871 relations with Indians would be governed by Acts of Congress and not by treaty. Elk v. Wilkins, 112 U. S. 94 (1884); In re Heff, 197 U. S. 488 (1905). The change in no way affected Congress’ plenary powers to legislate on problems of Indians, including legislating the ratification of contracts of the Executive Branch with Indian tribes to which affected States were not parties. Several decisions of this Court have long settled that proposition. In Choate v. Trapp, 224 U. S. 665 (1912), the Court held that tax exemptions contained in an 1897 agreement ratified by Congress between the United States and Indian tribes as part of a cession of Indian lands were enforceable against the State of Oklahoma, which was not a party to the agreement. In Perrin v. United States, 232 U. S. 478 (1914), the Court enforced a clause of an agreement ratified by Act of Congress that no intoxicating liquor should be sold on land in South Dakota ceded and relinquished to the United States, although South Dakota was not a party to the agreement. The Court expressly rejected the contention that the power to regulate the sale of intoxicating liquors upon all ceded lands rested exclusively in the State. Rather, because Congress was empowered, when securing the cession of part of an Indian reservation within a State, to prohibit the sale of intoxicants upon the ceded lands, “it follows that the State possesses no exclusive control over the subject and that the congressional prohibition is supreme.” Id., at 483. See also Dick v. United States, 208 U. S. 340 (1908). These decisions sustained the ratified agreements as the exercise by Congress of its “plenary power ... to deal with the special problems of Indians [that] is drawn both explicitly and implicitly from the Constitution itself. Article I, § 8, cl. 3, provides Congress with the power to 'regulate Commerce ... with the Indian Tribes/ and thus, to this extent, singles Indians out as a proper subject for separate legislation.” Morton v. Mancari, 417 U. S. 535, 551-552 (1974); see also Morton v. Ruiz, 415 U. S., at 236.
Once ratified by Act of Congress, the provisions of the agreements become law, and like treaties, the supreme law of the land. Congress could constitutionally have terminated the northern half of the Colville Indian Reservation on the terms and conditions in the 1891 Agreement, even if that Agreement had never been made. Mattz v. Arnett, 412 U. S. 481 (1973). The decisions in Choate, Perrin, and Dick, supra, settle that Congress, by its legislation ratifying the 1891 Agreement, constituted those provisions, including Art. 6, “Laws of the United States . . . made in Pursuance” of the Constitution, and the supreme law of the land, “superior and paramount to the authority of any State within whose limits are Indian tribes.” Dick v. United States, supra, at 353.
Ill
The opinion of the State Supreme Court also holds that in any event the implementing statutes cannot be construed to render Wash. Rev. Code §§ 77.16.020 and 77.16.030 inapplicable to Indian beneficiaries of the Agreement since the implementing statutes “make no reference to the provision [Art. 6] relied upon by the appellants.” 82 Wash. 2d, at 451, 511 P. 2d, at 1358. The opinion reasons: “[I]f it was thought that state regulation but not federal regulation would constitute an abridgement, an express provision to that effect should have been inserted, but only after the consent of the state had been sought and obtained.” Id., at 448, 511 P. 2d, at 1357. This reasoning is fatally flawed. The proper inquiry is not whether the State was or should have been a consenting party to the 1891 Agreement, but whether appellants acquired federally guaranteed rights by congressional ratification of the Agreement. Plainly appellants acquired such rights. Congress exercised its plenary constitutional powers to legislate those federally protected rights into law in enacting the implementing statutes that ratified the Agreement. No congressional purpose to subject the preserved rights to state regulation is to be found in the Acts or their legislative history. Rather, the implementing statutes unquali-fiedly, “earr[ied] into effect” and “ratified]” the explicit and unqualified provision of Art. 6 that “the right to hunt and fish . . . shall not be taken away or in anywise abridged.” State qualification of the rights is therefore precluded by force of the Supremacy Clause, and neither an express provision precluding state qualification nor the consent of the State was required to achieve that result.
IV
Finally, the opinion of the State Supreme Court construes Art. 6 as merely a promise by the United States that so long as it retained any ceded land and allowed others to hunt thereon, Indians would be allowed also to hunt there. 82 Wash. 2d, at 449-450, 511 P. 2d, at 1357-1358. But the provision of Art. 6 that the preserved rights are not exclusive and are to be enjoyed “in common with all other persons,” does not support that interpretation or affect the Supremacy Clause’s preclusion of qualifying state regulation. Non-Indians are, of course, not beneficiaries of the preserved rights, and the State remains wholly free to prohibit or regulate non-Indian hunting and fishing. The ratifying legislation must be construed to exempt the Indians’ preserved rights from like state regulation, however, else Congress preserved nothing which the Indians would not have had without that legislation. For consistency with the canon that the wording is not to be construed to the prejudice of the Indians makes it impermissible in the absence of explicit congressional expression, to construe the implementing Acts as “an impotent outcome to negotiations and a convention, which seemed to promise more and give the word of the Nation for more.” United States v. Winans, 198 U. S., at 380; Puyallup Tribe v. Department of Game (Puyallup I), 391 U. S. 392, 397-398 (1968). Winans involved a treaty that reserved to the Indians in the area ceded to the United States “the right of taking fish at all usual and accustomed places, in common with citizens of the Territory.” 198 U. S., at 378. Puyal-lup I considered a provision that “[t]he right of taking fish, at all usual and accustomed grounds and stations, is further secured to said Indians, in common with all citizens of the Territory . . . .” 391 U. S., at 395. The Court held that rights so preserved “may, of course, not be qualified by the State . . . .” Id., at 398; 198 U. S., at 384. Article 6 presents an even stronger case since Congress’ ratification of it included the flat prohibition that the right “shall not be taken away or in anywise abridged.”
V
In Puyallup I, supra, at 398, we held that although, these rights “may . . . not be qualified by the State, . . . the manner of fishing [and hunting], the size of the take, the restriction of commercial fishing [and hunting], and the like may be regulated by the State in the interest of conservation, provided the regulation meets appropriate standards and does not discriminate against the Indians.” The “appropriate standards” requirement means that the State must demonstrate that its regulation is a reasonable and necessary conservation measure, Washington Game Dept. v. Puyallup Tribe, 414 U. S. 44 (1973); Tulee v. Washington, 315 U. S. 681, 684 (1942), and that its application to the Indians is necessary in the interest of conservation.
The United States as amicus curiae invites the Court to announce that state restrictions “cannot abridge the Indians’ federally protected rights without [the State’s] demonstrating a compelling need” in the interest of conservation. Brief for United States as Amicus Curiae 16. We have no occasion in this case to address this question. The State of Washington has not argued, let alone established, that applying the ban on out-of-season hunting of deer by the Indians on the land in question is in any wray necessary or even useful for the conservation of deer. See Hunt v. United States, 278 U. S. 96 (1928).
The judgment of the Supreme Court of the State of Washington sustaining appellants’ convictions is reversed, and the case is remanded for further proceedings not inconsistent with this opinion.
It is so ordered.
The appellant husband is an enrolled member of the Confederated Tribes of the Colville Indian Reservation. Tribes that formed the Confederated Tribes included the Colville, Columbia, San Poil, Okanogan, Nez Perce, Lake, Spokane, and Coeur d’Alene. Appellant wife is a Canadian Indian and is not enrolled in the United States. We do not deal, however, with whether her case is for that reason distinguishable from her husband’s since the State Supreme Court drew no distinction between them. Moreover, ap-pellee State conceded at oral argument in this Court that reversal of the husband’s conviction would require reversal of the wife’s conviction. Tr. of Oral Arg. 22.
Washington Rev. Code § 77.16.020 provides in pertinent part:
“It shall be unlawful for any person to hunt . . . game animals . . . during the respective closed seasons therefor. . . .
“Any person who hunts . . . deer in violation of this section is guilty of a gross misdemeanor . . . .”
Section 77.16.030 provides in pertinent part:
“It shall be unlawful for any person to have in his possession . . . any ... game animal.. . during the closed season ...
“Any person who has in his possession . . . any . . . deer ... in violation of the foregoing portion of this section is guilty of a gross misdemeanor . . . .”
The original reservation was over 3 million acres “bounded on the east and south by the Columbia River, on the west by the Okanagan River, and on the north by the British possessions.” Exec. Order of July 2, 1872; 1 C. Kappler, Indian Affairs, Laws and Treaties 916 (2d ed. 1904); see also Seymour v. Superintendent, 368 U. S. 351, 354 (1962).
Article 6 provided in full:
“It is stipulated and agreed that the lands to be allotted as aforesaid to said Indians and the improvements thereon shall not be subject, within the limitations prescribed by law, to taxation for any purpose, national, state or municipal; that said Indians shall enjoy without let or hindrance the right at all times freely to use all water power and water courses belonging to or connected with the lands to be so allotted, and that the right to hunt and fish in common with all other persons on lands not allotted to said Indians shall not be taken away or in anywise abridged.”
The status of the southern half of the Colville Reservation was considered in Seymour v. Superintendent, supra. At issue in this case are the residual rights to hunt and fish on the northern half preserved by the above Art. 6.
The Colville Indian Commission was composed of Chairman Fullerton and Commissioners Durfur and Payne. The Commission first met on May 7, 1891, with representatives of the Confederated Tribes at Nespelem, Wash., on the reservation to discuss “a sale of a part of Reservation. . . .” During succeeding days, Ko-Mo-Del-Kiah, Chief of the San Poil, strongly opposed the sale of any part of the reservation, but Antoine, Chief of the Okanogan and great-grandfather of appellant Alexander Antoine, Moses, Chief of the Columbia, and Joseph, Chief of the Nez Perce, favored the proposed 1891 Agreement as fair. At a later meeting on May 23 at Marcus on the reservation, Barnaby, Chief of the Colville, and the Chief of the Lake agreed to the proposed sale. Minutes of Colville Indian Commission Concerning Negotiation for the 1891 Agreement of Sale, National Archives Document 21167.
The delay in approval was occasioned by the initial reluctance of the House to ratify the Agreement without certain changes, 23 Cong. Rec. 3840 (1892), and by doubts raised in the Senate whether the Indians had title to the reservation, since it was created by Executive Order. See S. Rep. No. 664,52d Cong., 1st Sess.,2 (1892). The Interior Department reported some years later that the doubts were unfounded. S. Rep. No. 2561, 59th Cong., 1st Sess., 137, 139 (1906). A bill passed by the House in 1891 replaced the $1,500,000 lump sum with a payment of $1.25 per acre, to be paid from the proceeds of sales of land opened for homesteading. The Senate disagreed, however, and passed a bill that ultimately became the Act of July 1, 1892. That Act makes no mention either of the consideration to be paid, or of the hunting and fishing rights preserved. Many protests were thereupon made that Congress had failed to live up to the terms of the Agreement. These included protests from the Department of the Interior, S. Rep. No. 2561, supra, at 137, 139, and from Chairman Fullerton, who had become Chief Justice of the Supreme Court of Washington. In a letter, id., at 140, the Chief Justice said:
“It may be that my relations to this transaction have somewhat warped my judgment, but when I recall the impassioned appeals made by some of the aged members of these remnant bands, calling upon their people and upon the heads of the tribes not to sign away their lands, even though the compensation offered was ample, on the ground that it was their last heritage and their last tie to earth, I can not help a feeling of bitterness when I remember that the Government, whom we represented to them as being just and honorable, took away their land without even the solace of compensation.”
The many protests finally bore fruit and Congress enacted the Act of June 21, 1906, and the five subsequent installment Acts. The Colville claims required the services of 16 lawyers from the States of Washington, Pennsylvania, and Georgia, and the District of Columbia. They recovered judgments against the United States for their services in the Court of Claims. Butler and Vale v. United States, 43 Ct. Cl. 497 (1908).
Article VI, cl. 2, of the Constitution, the Supremacy Clause, provides:
“This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.”
The Act of Mar. 3, 1871, 16 Stat. 544, 566, now codified as 25 U. S. C. §71, provides:
“No Indian nation or tribe within the territory of the United States shall be acknowledged or recognized as an independent nation, tribe, or power with whom the United States may contract by treaty; but no obligation of any treaty lawfully made and ratified with any such Indian nation or tribe prior to March 3, 1871, shall be invalidated or impaired.”
Former Commissioner of Indian Affairs Walker summarized the struggle as follows:
“In 1871, however, the insolence of conscious strength, and the growing jealousy of the House of Representatives towards the prerogative — arrogated by the Senate — of determining, in connection with the executive, all questions of Indian right and title, and of committing the United States incidentally to pecuniary obligations limited only by its own discretion, for which the House should be bound to make provision without inquiry, led to the adoption, after several severe parliamentary struggles, of the declaration . . . that ‘hereafter no Indian nation or tribe within the territory of the United States shall be acknowledged or recognized as an independent nation, tribe, or power, with whom the United States may contract by treaty.’ ” Federal Indian Law 211-212, citing F. Walker, The Indian Question (1874).
Washington Rev. Code § 37.12.060, which assumes limited jurisdiction over Indians, expressly provides that the law shall not deprive any Indian of rights secured by agreement.
“Nothing in this chapter . . . shall deprive any Indian or any Indian tribe, band, or community of any right, privilege, or immunity afforded under federal treaty, agreement, statute, or executive order with respect to Indian land grants, hunting, trapping, or fishing or the control, licensing, or regulation thereof.” (Emphasis added.)
Appellants apparently claim no right to hunt on fenced private property. The State Supreme Court stated:
“Counsel . . . conceded in oral argument that the present owners of land in the northern half of the reservation have the right to fence their land and exclude hunters. Nevertheless they maintain that state regulation of the right to hunt is an abridgment of that right . . . .” 82 Wash. 2d 440, 448, 511 P. 2d 1351, 1356 (1973).
A claim of entitlement to hunt on fenced or posted private land without prior permission of the owner would raise serious questions not presented in this case.