Union
About Union
Union, South Dakota, first appears in the United States federal census in 1870, when it recorded a population of 3,507. At the most recent census, in 2020, its population stood at 16,811.
The county's recorded population has risen across the decades to its highest level in 2020.
On the ground today, 16 places are listed on the National Register of Historic Places.
Population by decade
Population data from the United States decennial census, U.S. Census Bureau (public domain).
Historic places in Union
National Register of Historic Places listings in Union, South Dakota.
Other counties in South Dakota
Explore census history and historic records for more South Dakota counties.
Everything a full report reveals about Union County, South Dakota
This page charts the census history of Union County, South Dakota. A full Aubrey report for an address here pulls together everything the historical record holds about the ground, from the earliest settlement to the twentieth century:
Every location is different. Not every section appears for every place, only what the historical record actually holds turns up in a report.
Explore South Dakota records
Frequently asked about Union
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