After the elections, the first General Assembly convened in the Missouri Hotel at Main and Morgan in St. Louis on September 19, 1820.
Members chose James Caldwell of Ste. Genevieve as speaker of the house, and John McArthur, clerk. Silas Bent was president pro tem of the Senate. Gov. McNair appointed all other state officials, including John D. Cook as one of the Supreme Court justices.
State legislatures elected U. S. Senators until the ratification of the 17th Amendment in 1913, so the General Assembly made these selections at the first meeting. The body elected David Barton, who had been chairman of the constitutional convention, without opposition.
The second contest was between Thomas Hart Benton, Nathaniel Cook, Henry Elliott, John Rice Jones, and J. B. C. Lucas. Lucas and Benton were the front-runners. Lucas had political baggage from his service on the board of land commissioners, having opposed confirmation of many Spanish grants to early residents. Benton was unpopular, but prevailed with the influence of large land claimants and the expedient of his fatally-ill friend Senator Daniel Ralls being carried into the house from his sickbed to cast a vote.
Among 64 more routine acts, the assembly fixed the seat of government at St. Charles until 1826 after lengthy debate, passed acts for the organization of 10 new counties, and organized the state into four judicial districts.
Several attempts to propose state constitutional amendments failed, and Governor McNair had to call a special session in 1821 to accomplish that. So, with a shaky start, the first Missouri General Assembly adjourned.
