James Donald Cameron (May 14, 1833 – August 30, 1918) was an American banker, businessman and Republican politician who served as Secretary of War in the cabinet of President Ulysses S. Grant from 1876 to 1877 and represented Pennsylvania in the United States Senate from 1877 to 1897.

[1][a] During Cameron's tenure, the military was challenged by the Great Sioux War and by the threat of a second Southern secession after the controversial 1876 election of President Rutherford B. Hayes.

Cameron proved to be an energetic administrator and his appointment as Secretary of War launched his lengthy political career in the Senate.

As an executive of the Northern Central Railway during the American Civil War, Cameron managed the flow of supplies and soldiers from the northeastern states to Washington, D.C., and Virginia, including efforts to keep the railroad open despite Confederate attempt to damage or destroy it.

Cameron's predecessor, Alphonso Taft, had initially replaced William W. Belknap, who had abruptly resigned over taking profit payments from the Fort Sill tradership.

When gold was discovered in the Black Hills, miners began to invade Indian territory given by the federal government to the Sioux tribe under the Fort Laramie Treaty of 1868.

In addition, the federal government planned to put a route of the Northern Pacific Railroad through the Sioux and Cheyenne buffalo hunting grounds.

[4] After negotiation for the sale of Sioux land failed in May 1875, President Grant ordered all non-treaty bands to return to the reservation.

This was to prevent another massacre that had taken the lives of Colonel George Armstrong Custer and the 7th Cavalry at the Battle of the Little Bighorn.

[7] Secretary of War Cameron allowed military troops stationed in both contested states to be at the disposal of Republican politicians.

[7] In his 1876 Annual Report Cameron mentioned that General of the Army William T. Sherman, notifying the War Department, said Southern states threatened to secede from the Union if Tilden was not elected.

[8] These stationed troops and the delicate and prudent actions of both generals, Augur and Ruger, to keep peace, prevented a second Civil War.

[11] Adopting his father's method, Cameron's strength as a politician relied on working inside the antechamber, committees, and caucuses to obtain his goals.

[11] Cameron would ally with other pro-free silver Republicans to block the passage of the Federal Elections Bill, that ensured African Americans' voting protection rights in the Solid South.

[11] On the whole, Cameron's nearly twenty years in the Senate remained undistinguished while for the most part he voted on the Republican Party line.

Cameron was part of a transitional period when civilian control was reestablished over the War Department during the end of Reconstruction.

As Senator, Cameron was known as a quiet, but powerful, political boss during the Gilded Age, who supported African American voting rights.

Cameron followed in his father Simon's footsteps, protecting the railroad interests of the PPR, in control of Pennsylvania Republican Party politics.

"[11] However, Meneely admired Cameron for breaking from the rest of his party and opposing the African American 1890 voting rights legislation, "Force Bill", saying that Cameron "showed admirable and courageous independence," and demonstrating the racist tendencies common among historians of the era.

[11] Meneely concluded that Cameron was "[t]horoughly honest in personal matters" and "held in high regard by his friends".