Blair, the county seat of Washington County, was platted in 1869 as the Sioux City and Pacific Railroad extended into the area and was named for railroad magnate John Insley Blair; it incorporated as a city in 1872 and has anchored the county ever since, part of the greater Omaha-Council Bluffs metro area.

With roughly 7,800-8,000 residents, Blair is Washington County's largest city and historical hub, home for decades to Dana College, the site of a landmark 1873 Supreme Court railroad case, and more recently the community that endured and is recovering from an EF4 tornado in April 2024.