On November 2, 1889, North Dakota and South Dakota were admitted to the Union as the 39th and 40th states. President Benjamin Harrison signed the statehood proclamations in such a way that the exact order is traditionally treated as simultaneous. The Dakotas had grown in population through farming, railroads, and immigration, which helped them meet the requirements for statehood. Their admission increased the number of states represented in Congress and shifted political balances in the Senate. The two states developed distinct identities but shared similar agricultural economies and frontier histories. Their statehood reflected the broader trend of organizing the remaining western territories into states in the late nineteenth century.
