Vilas County was created in 1893 when the state legislature divided Oneida County. the new county was named after William Vilas, who among other things, had served a term as a U.S. Senator representing Wisconsin. In Dane County, he is remembered for endowing the Henry Vilas Zoo, which was named for his son who died at an early age.
The boundaries of Vilas County were modified in 1897 and again in 1905. Eagle River has been the county seat since the county was created.
The Vilas County courthouse is located at 330 Court Street in Eagle River.