"Reserved the area west of the Missouri River and east of the Rockies for the 'absolute and undisturbed use' of the Sioux."1
The Treaty of Fort Laramie created the Great Sioux Reservation; what you don't find about it in Farm, Field, and Fireside could be as significant as what you do find. Begin with keywords like, "fort laramie", or "red cloud*".
Other tribes assigned lands by the treaty: Crow, Assinabin, "Gros Ventre", Mandan, Arikara, Blackfeet, Cheyenne, and Arapahoe.2
"The Sioux Bill divides the Great Sioux Reservation into six smaller reservations. The law also opens nine million acres of former reservation land to settlement by whites."3
Utley, Robert M. "The Land Agreement." The Last Days of the Sioux Nation. 2d ed. New Haven: Yale University Press, 2004. 40-59.
Terms: "sioux bill", "sioux agreement".
Use date ranges (e.g. 1887-1889) and simple keyword searches like: sioux AND reservation.
The Sioux Bill created 6 news reservations: "Standing Rock", "Pine Ridge", Rosebud, "Cheyenne River", "Crow Creek", and "Lower Brulé"--all tied to previously existing agencies. Try these names as keywords.
S. Exec. Doc. No. 1. 49th Congress, 1st Sess. (Dec. 10, 1885).
Map showing James River country and limits of Sioux lands, Dakota Territory. Serial Set No. 2333, Sess. Vol. No. 1. Map No. 3.
S. Exec. Doc. No. 1. 49th Congress, 1st Sess. (1885).
Map of the old Winnebago and Sioux Indian reservations on the left bank, Missouri River, Dakota Territory. Serial Set No. 2333, Sess. Vol. No.1.
H. Exec. Doc. No. 1, Pt. 5, Vol. 1. 50th Congress, 2d Sess. (1888).
Report of the Secretary of the Interior: The Great Sioux Reservation. Serial Set No. 2636, Sess. Vol. No. 10. PP. LVI-LXVI; Appendices CXLV-CLXXVII; P. 120. And tables.
H. Exec. Doc. No. 1 Pt. 5, Vol. 2. 50th Congress, 2nd Sess. (1888).
Report of the Secretary of the Interior: Commission to the Sioux in Dakota. Serial Set No. 2637, Sess. Vol. No.11. PP. PP. LXXIII-LXXV. Report of the Cheyenne River Agency: PP. 25-29. Report of the Crow Creek and Lower Brulé Agency: PP. 29-36. Report of the Devil's Lake Agency: PP. 36-42. Report of the Pine Ridge Agency: PP. 46-53. Report of the Rosebud Agency: PP. 54-56. Report of the Sisseton Agency: PP. 56-58. Report of the Standing Rock Agency: PP. 59-64. Report of the Yankton Agency: PP. 64-80. Report of the Santee Agency: PP. 170-178. Sioux Bill (reprinted): PP. 294-301. And tables.
S. Exec. Doc. No. 17. 50th Congress, 2d Sess. (December 14, 1888): Map showing boundaries of the proposed diminished Sioux Indian reservations in Dakota. Serial Set No. 2610, Sess. Vol. No. 1. Map No. 1.
"Sioux Bill." March 2, 1889. 50th Cong., 2d sess. United States Statutes at Large 25, pt.2, ch.405, pp.888-899.
An Act To Divide a Portion of the Reservation of the Sioux Nation of Indians in Dakota into Separate Reservations and to Secure the Relinquishment of the Indian Title to the Remainder."
Statutes at Large 25 available online. (For this act, Jump to page 935 in the PDF.)
S. Doc. No. 67. 55th Congress, 2nd Sess. (1898).
Letter from the Secretary of the Interior: Santee Sioux of Nebraska and Flandreau Sioux of South Dakota. Serial Set No. 3592, Sess. Vol. No.3.
S. Rpt. No. 440. 60th Congress, 1st Sess. (1908).
Allotments to Rosebud Sioux Indian children. Serial Set No. 5219, Sess. Vol. No.2.
You'll find many other sources in the Library for this topic. Below are some examples of newspaper articles on the Sioux Reservation. We've organized them chronologically. For much more like this, search in our Historical Newspaper Collections using date ranges (e.g. 1887-1889) and simple keyword searches like: sioux AND bill or sioux AND reservation.
1887: March 7. Chicago Daily Tribune. "The Sioux Reservation: How the Bill to Open Up the Land to Settlement Failed: Holman to Blame." P.3.
1887: Nov. 3. New York Times. "Sitting Bull's Rival: Chief Gall's Speech at a Council of the Sioux." P.3.
1887: Dec. 31. New York Times. "Sitting Bull Will Not Go." P.4.
1888: Jan. 1. Chicago Daily Tribune. "21 Million Acres: The Vast Tract of Land Which the Dawes Bill Will Throw Open." P.15.
1888: Jan. 1. Chicago Daily Tribune. "What the Sioux Want: Not the Earth, But What They Consider Their Share of It." P.15.
1888: Jan. 7. Chicago Daily Tribune. "The Sioux Reservation." P.2.
1888: Feb. 10. Chicago Daily Tribune. "Opening the Sioux Reservaton." P.6.
1888: Feb. 15. Chicago Daily Tribune. "Division of the Sioux Reservation." P.9.
1888: Feb. 24. Washington Post. "Cheyennes Excited." P.6.
1888: March 10. Chicago Daily Tribune. "The Sioux Reservation Bill: What the Indian Chiefs Think of the Measure." P.6.
1888: May 11. New York Times. "The Indians Will Sign." P.1.
1888: May 23. New York Times. "The Sioux Reservation: Prospects That the Country Will Soon Be Open For Settlement." P.3.
1888: Aug. 7. Washington Post. "The Red Men." P.4.
1888: Aug. 16. Goodale, Elaine. "Will the Indians Sign?" Independent: Devoted to the Consideration of Politics... P.6.
1888: Aug. 27. Chicago Daily Tribune. "At Crow Creek Agency: The Sioux Commissioners Still Laboring with the Indians." P.6.
1888: Aug. 29. New York Times. "Crow Creeks in Council: Another Pow-Wow Regarding the Sioux Bill." P.1.
1888: Sept. 2. Chicago Daily Tribune. "Counciling with Indians." P.12.
1888: Sept. 2. New York Times. "News of the Indians." P.6.
1888: Sept. 8. New York Times. "The Fate of the Sioux Bill." P.2.
1888: Sept. 8. Chicago Daily Tribune. "Commissioners at Lower Brule: The Sioux at This Agency More Favorably Disposed to the Bill." P.6.
In this section are other events treated in the Farm, Field, and Fireside collection.
With the Black Hills Act, Congress opened the Black Hills by revoking terms of the 1868 Treaty of Fort Laramie.
S. Exec. Doc. No. 2. 44th Cong., Special Senate Sess. (1875).
Message from the President of the United States, transmitting, in answer to a Senate resolution of March 15, 1875, information in relation to the Black Hills country in the Sioux Indian reservation. March 17, 1875. Serial Set No. 1629, Sess. Vol. No. 1.
"Should Congress open up the country for settlement, by extinguishing the treaty rights of the Indians, the undersigned will give a cordial support to the settlement of the Black Hills"--Lieutenant-General P.H. Sheridan.
"Black Hills Act." February 28, 1877. 44th Cong., 2d Sess. United States Statutes at Large 19, ch. 72, pp. 254-64.
"An act to ratify an agreement with certain bands of the Sioux Nation of Indians."
Statutes at Large 19 available online. (For this act, jump to page 274 in the PDF.)