The Territory of Colorado was a historic, organized territory of the United States that existed between 1861 and 1876. Its boundaries were identical to the current State of Colorado. The territory ceased to exist when Colorado was admitted to the Union as a state on August 1, 1876. The territory was organized in the wake of the 1859 Pike's Peak Gold Rush, which had brought the first large concentration of white settlement to the region. The organic act[5] creating the territory was passed by Congress and signed by President James Buchanan on February 28, 1861, during the secessions by Southern states that precipitated the American Civil War. The organization of the territory helped solidify Union control over a mineral rich area of the Rocky Mountains.
Statehood was regarded as fairly imminent, but territorial ambitions for statehood were thwarted at the end of 1865 by a veto by President Andrew Johnson. Statehood for the territory was a recurring issue during the Ulysses Grant administration, with Grant advocating statehood against a less willing Congress during Reconstruction.