When and why did House parties identify exclusive committees? The nexus of parties and standing committees defines the distribution of power in the U.S. House of Representatives, shapes legislators’ careers, and affects Congress's ability to address the nation's problems. Yet, political science provides inadequate and often misleading characterizations of the parties and the most important standing committees. We provide missing detail and offer a historical perspective on party efforts to arrange standing committees in the period since the revolt against Speaker Joseph Cannon in 1909–1910. Our narrative offers a foundation for explaining party efforts to regulate committee membership and meet legislators’ demands. For the first time, we define three periods in committee assignment limitations. In doing so, we place key events in historical context: We report that the modern exclusive committees (Appropriations, Rules, and Ways and Means) did not become defined until the 1950s; the identification by the two parties of a larger set of exclusive committees for which a one-assignment limitation applied began decades earlier; the Legislative Reorganization Act of 1946 placed a one-assignment limitation in House rules that had been party practice for three decades by then. In recent decades, deep partisanship has been accompanied by a loosening, not tightening, of restrictions. In fact, there are no fully exclusive committees remaining in practice.