In 1919, President Woodrow Wilson headed to France to negotiate the terms of the peace treaty to end World War I. The treaty included a covenant establishing the League of Nations, an international organization for collective security and dispute resolution. The Treaty of Versailles marked the first time a U.S. president had ever left the country personally to negotiate a treaty. However, it also became the first peace treaty ever rejected by the Senate.

A League of His Own

President Wilson first proposed the idea for an international peace organization in 1918 to Congress. The League of Nations became the most important part of the Versailles Treaty for the president -- he even appeared personally to argue for ratification at a meeting of the Senate Foreign Relations Committee. However, during the treaty's negotiations Wilson had ignored the Senate and hadn't included any senators in the team he took with him to France. Although American public opinion supported ratification of the treaty and U.S. membership in the League, Wilson faced strong opposition among the spurned senators, primarily Henry Cabot Lodge, the Republican Senate Majority Leader and Chairman of the Senate Foreign Relations Committee.

Irreconcilable Differences

The 1918 midterm elections had given the Republican Party control of the Senate. Senator Lodge, who became majority leader, had a long and contentious rivalry with the Democratic president. Despite the fact that 32 state legislatures had passed resolutions in favor of ratifying the Versailles Treaty, Republicans in the Senate had grave concerns about the proposed League of Nations. At least six Republican senators, the "Irreconcilables," refused to approve U.S. membership in the League under any circumstances. Aside from traditional American fears of entanglement in European political affairs, they feared the League would reduce America's ability to defend itself.

Lodge's Reservations

Senator Lodge supported President Wilson's treaty, provided amendments were made that would preserve Congressional war powers. The other Republicans who supported Lodge made up a slim majority of senators. Wilson appeared before the Committee in an effort to win over some of the more moderate Republicans, but he was unwilling to compromise on any of the commitments required for membership in the League of Nations. When Lodge's attempts to pass the treaty with amendments failed, he submitted the treaty for another vote in the Senate with 14 reservations attached. Prime among them was a condition that the U.S. would not act to assist another League member in defending its territory without congressional approval.

A House Divided

Ratification of the Versailles Treaty had reached an impasse. While most Democrats in the Senate supported the president, they were a minority -- and many of them privately agreed with Lodge's reservations. The first ratification attempt, including Lodge's accompanying amendments, failed because Democrats who supported the president's version of the treaty were joined by the Republican Irreconcilables who opposed the treaty in any form. A compromise effort by Democrats and moderate Republicans brought about a second vote. The 49 votes in favor of ratification came seven votes short of the two-thirds needed to ratify the treaty. The U.S. ultimately signed a separate peace treaty with Germany and never joined the League of Nations.