On Wednesday, Sen. Bernie Sanders (I-Vt.) suspended his campaign for president, clearing the way for former vice president Joe Biden to be the Democratic nominee and likely deeply dividing Sanders’s devoted supporters and even his advisers.

Some advisers and supporters will probably cheer the move, seeing it as a way to avoid a debilitating party feud that could hurt Biden in the fall campaign against President Trump. Others, however, wanted to see Sanders take his fight to the Democratic convention to give his supporters a chance to “vote for that alternative vision,” in the words of top Sanders ally Larry Cohen.

By making this choice, Sanders spotlighted the dilemma that often faces populist insurgent movements: Do they make peace with the political establishment, seeing it as the most likely path to bring their ideas into mainstream American politics, or do they hold out, focusing on building their movement’s strength? The populist People’s Party faced just this quandary in the summer of 1896 as delegates met in St. Louis for the party convention.

Four years earlier, the People’s Party had reached unimaginable heights. Meeting in Omaha over the July 4 weekend in 1892, it unfurled a party platform calling for government ownership of the railroads, a graduated income tax and an inflationary approach to monetary policy to lift the burden of debt and bankruptcy crushing many farmers and ranchers.

The Omaha Platform advanced the populist belief that “the powers of government” should be fully deployed to eradicate the “oppression, injustice and poverty” that flourished across the country. As its presidential candidate, the party nominated James B. Weaver of Iowa, a veteran of third-party politics who had served three terms in the House of Representatives.

The establishment press reacted with scorn. The Democratic St. Paul Globe mocked the Omaha Platform’s “perfervid rhetoric,” while the New York Times called it a “strange document” whose “proposed remedies for the alleged evils are as crazy as the statement of the evils.” The party would carry no state “whose population is not made up of ‘cranks,’” the Times predicted, but Weaver proved otherwise. Taking the then-unusual step of campaigning across the country, Weaver led the People’s Party to victories in Kansas, Colorado, Nevada and Idaho. It was the first time a third party had earned votes in the electoral college since 1860.

The success proved short-lived. In 1894, in the midst of a depression, voters angry with Grover Cleveland’s administration turned to the Republicans rather than the People’s Party. The Republican wave produced a whopping 130-seat gain in the House, swamping Democrats and populists alike — including Weaver, who was running for Congress in Iowa.

Two years later, populists faced an additional challenge as they prepared for their convention on July 22: to join forces with Democrats or remain independent?

Democrats meeting in Chicago earlier that month had nominated former congressman William Jennings Bryan after the Nebraskan delivered a historic speech warning banking interests that “you shall not crucify mankind upon a cross of gold.” Swayed by Bryan, Democrats abandoned Cleveland’s small-government conservatism in favor of a platform that called for inflationary monetary policies, a graduated income tax and enhanced enforcement powers for the Interstate Commerce Commission — positions clearly influenced by the People’s Party program.

That left the third party with a choice: Should it align with the Democrats and Bryan or go its own way? Advocates who wanted to present an alternative choice to Democrats and Republicans — characterized at the time as a “middle of the road” course — argued they “should make no coalition with either old party, and should avoid fusion as they would the devil,” in the words of Georgia firebrand Tom Watson.

Weaver and others, however, believed such a course threatened the causes for which the third party stood. “Nothing grows in the middle of the road,” argued Weaver, who worked behind the scenes to push the People’s Party toward the Democrats by nominating Bryan.

Bitterly divided, the People’s Party delegates settled on an awkward compromise: They first selected Watson to be their vice-presidential nominee to placate independent-minded delegates. But then, after Weaver urged them to cast aside partisan considerations to advance “the sacred cause which is at stake in this campaign,” they chose Bryan as their presidential nominee.

The choice left many disappointed. A delegate from West Virginia voiced his frustration: “I came here to prevent this convention from falling into the hands of the Democratic Party.”

The decision to nominate Bryan ultimately spelled doom for the People’s Party as an independent political organization and failed to stop Republican William McKinley from winning the presidency in the fall. The party’s factions nominated rival candidates in 1900 and reunited behind Watson in 1904 but never rivaled the success Weaver achieved in 1892 and eventually faded from the scene.

Bryan ran twice more for the White House, losing both times, but redirected the Democratic Party toward many of the goals of the Omaha Platform. While Watson resolutely refused to unite with the Democrats, a number of populists, including Weaver, entered the party’s ranks. Years later, it became clear that Bryan was a transformative figure who, in the words of historian Michael Kazin, “did more than any other man — between the fall of Grover Cleveland and the election of Woodrow Wilson — to transform his party from a bulwark of laissez-faire into the citadel of liberalism we identify with Franklin D. Roosevelt and his ideological descendants.” But that is a historical judgment that could not have been foreseen in the immediate aftermath of Bryan’s loss in 1896.

The relationship of the Sanders campaign to the Democratic Party was fundamentally different from the position of the People’s Party in 1896. As Kazin has argued, Sanders was engaged in the latest chapter in a half-century internecine struggle. And although he has long been an independent, Sanders has connections and ties to the Democratic establishment that make his position blurrier: He is both a “traditional politician and a movement leader,” as The Washington Post’s Sean Sullivan writes.

These connections probably left him mindful of the need to avoid deepening divisions in the party, especially in a moment of crisis. They also explain the warm words Biden had for Sanders upon the suspension of the latter’s campaign, crediting Sanders with creating a movement and moving issues such as income inequality, universal health care and climate change to the center of the debate.

But like the People’s Party nomination of Bryan in 1896, Sanders’s decision to avoid forging ahead is likely to rankle those of his supporters who view establishment Democrats like Biden as part of the problem in U.S. politics. Like the middle-of-the-road populists who backed Tom Watson, they believe bringing issues to the center of the debate is not enough, and perhaps nor is achieving half-measures.

“If we lose to Trump then hopefully within the next four years maybe an [Alexandria Ocasio-Cortez] or Rashida Tlaib would be able to run,” one “Bernie or Bust” voter told the Guardian. “Maybe there would be a better chance to save the planet.”

Only time will tell if Sanders made the right judgment for advancing his cause. But as the People’s Party demonstrated, it would have been impossible to pick a course that all of his supporters would have applauded.