On March 26, 1804, President Thomas Jefferson signed into law "An Act erecting Louisiana into two territories, and providing for the temporary government thereof." This legislative act was a crucial step in the administration and organization of the vast lands acquired through the Louisiana Purchase. While the event itself occurred in Washington D.C., its implications directly impacted the future of what would become Montana.

The division of the Louisiana Purchase into the Territory of Orleans and the District of Louisiana set the stage for subsequent territorial formations and westward expansion, eventually leading to the exploration, settlement, and statehood of Montana. This act is a foundational moment in the broader history of the American West and, by extension, Montana, as it established the initial governmental framework for the newly acquired lands.