Hamilton County was formed in 1867 and was named for Alexander Hamilton, the first Secretary of the Treasury. Area Page: Eastern South Nebraska AreaCounty Seat: Aurora NebraskaLicense Platte Prefix: 28Census 2010: 9,124Cities Towns in the County: Aurora NebraskaCounty Map with Cities: Hamilton County MapWebsite - County: Hamilton County Nebraska Official WebsiteWebsite - County Fair: Hamilton County Nebraska County Fair