Skip Content
U.S. Flag

Missouri Compromise Ushers in New Era for the Senate

March 3, 1820

Henry Clay of Kentucky

The Missouri Compromise represents a major milestone in American history. Passed by Congress on March 3, 1820, the compromise temporarily settled a divisive national debate over whether new states would permit or prohibit slavery. Perhaps less known, but equally important, is the fact that this landmark legislative compromise also set the stage for a new era in Senate history

In the early years of congressional history, the House of Representatives dominated the legislative process, leaving the Senate to operate in its shadow. Americans found the more rambunctious House—then dominated by the nation’s most skilled politicians—to be far more interesting than the quietly deliberative Senate. Henry Clay, for example, served two short terms in the Senate beginning in 1806, but soon found its chamber too sedate for his grand ambitions. In 1811 he moved to the House, and was promptly elected Speaker on his very first day in office.

Speaker Clay was on hand in 1818 when Missouri became the first territory west of the Mississippi River to apply for statehood. When the statehood bill arrived in the House, a New York representative offered an amendment to prohibit slavery in the new state. The House approved the amended bill, but just barely, and with a vote that reflected the nation’s growing sectional crisis. “You have kindled a fire which all the waters of the ocean cannot put out,” declared one lawmaker. When the bill arrived in the Senate, pro-slavery senators struck out the offending amendment. The House refused to concur with the Senate’s version of the bill, a stalemate ensued, and the statehood measure died.

Missouri renewed its application for statehood in 1820. Once again, a contentious debate stirred up anger and bitterness over a score of issues—industrial development, trade and tariff policies, and—always—slavery. Seeking a way to settle the dispute and prevent disunion, Speaker Clay promoted a compromise to allow slavery in Missouri while simultaneously admitting Maine as a free state. This so-called Missouri Compromise drew a line from east to west along the 36th parallel, dividing the nation into competing halves—half free, half slave. The House passed the compromise bill on March 2, 1820.

The next day, pro-slavery advocates in the House moved to reconsider the vote. In what one Clay biographer called the “neatest and cleverest parliamentary trick ever sprung in the House,” Speaker Clay declared the motion out of order until routine business was completed, then discretely signed the Missouri bill and sent it to the Senate for approval. When his opponents again raised their motion later in the day, Clay blithely announced that the compromise measure had already gone to the Senate and had already been passed.

Why was the Missouri Compromise so important to the Senate? It maintained a delicate balance between free and slave states. On the single most divisive issue of the day, the U.S. Senate was equally divided. If the slavery question could be settled politically, any such settlement would have to happen in the Senate. That realization inspired men like Henry Clay—and Daniel Webster and John C. Calhoun—to join the Senate, shining the spotlight of public attention on a new stage and a new era of debate.

Ironically, it was the astute maneuvering of Speaker Henry Clay that helped bring about this new era of Senate debate, creating a legislative forum in which Senator Henry Clay would soon forge other Union-saving compromises.