On November 2, 1889, President Benjamin Harrison signed the papers that made North Dakota and South Dakota the 39th and 40th states of the United States. The Dakota Territory, split by the river that gives the two states their names, entered the Union as a pair.
The timing was political. Harrison kept the two proclamations face down and signed them without saying which was first, so neither state could claim clear seniority over the other. Both joined the same day.
The land was hard. The railroads shaped it. Few sets existed.
Settlers had poured onto the plains through the 1870s and 1880s, drawn by rail lines and by the promise of farmland that the federal government offered in parcels, and the new states arrived in the middle of a rush of admissions that also brought Montana and Washington into the Union that year.
The two states built their governments on wheat, cattle, and grain terminals, and they have kept the shared date as Statehood Day ever since. The puzzle of which Dakota came first was never settled, and both sides decided they were content to let it stand.
Harrison faced a crowded field of new states that year, and the pair from the Dakota Territory gave the northern plains a voice in a union that had just crossed the Mississippi in force. The two capitals, Bismarck and Pierre, grew from fort towns into seats of government within a decade.