On November 13, 1890, troops moved into South Dakota, a military movement that would result six weeks later in the Wounded Knee Massacre. The president sent soldiers to South Dakota, the largest movement of troops since the Civil War, in the midst of a midterm election campaign that looked bad for his party.

In 1890, Republican president Benjamin Harrison was facing a revolt in the midterms. The Republicans had risen before the Civil War as the party of ordinary farmers and workers, and had fought the Civil War to take control of America out of the hands of the nation’s wealthy slave owners. But after the war, Republicans had gradually swung behind the nation’s rising industrialists—men like Andrew Carnegie and J. D. Rockefeller—and propped up their industries with tariff walls that enabled them to keep consumer prices high. Voters, who hated the tariffs, increasingly backed the Democrats, who promised to lower them. Democrats had won the House of Representatives in 1874, and in 1884, Grover Cleveland became the first Democrat elected to the White House since the 1850s. Horrified Republicans had pulled out all the stops in 1888 to reclaim the government for their party.

In the 1888 election, they tapped large donors to fill the Republican war chest, then used the money to flood newspapers with pro-tariff arguments, warning that the Democrats were radicals who would destroy the economy, and promising that Republicans themselves would “reform” the tariff. But while Republicans’ strategy won the House of Representatives, it didn’t work for the presidency: Cleveland garnered about 100,000 more votes than the Republican candidate, Benjamin Harrison. So Republican operatives swung the election in the Electoral College, striking a backroom deal with the New York delegation to win an electoral victory. When the pious Harrison mused that Providence had given him the win, one of his operatives grumbled, “Providence hadn’t a damn thing to do with it. A number of men were compelled to approach the penitentiary to make him President.”

Harrison’s men recognized that they could not continue to hold power under the current system. So they rigged it. They admitted six new western states to the Union, the largest bulk admission of states since the original thirteen. In 1889, they split the huge Territory of Dakota into two parts—North Dakota and South Dakota—and added both to the Union, along with Washington and Montana. They fully expected the new states to vote Republican: when Montana went Democratic, they claimed the vote was fraudulent and replaced the Democrats with Republicans. In 1890, they added Wyoming and Idaho, moving so fast in the latter case that they had to call for volunteers to write a constitution that voters approved only months later. It was unclear that any of these western states even had enough people in them to justify statehood, but Republicans insisted the forthcoming 1890 census would prove that admitting them had been warranted. Administration men boasted that the admission of the new states would guarantee Republican control of the Senate and the Electoral College for the foreseeable future.

With this security in place, party leaders actually raised, rather than lowered, tariff rates just before the November election. They insisted that stronger protections for business would help workers by making the economy boom. ...