Vigo County ( or ) is a county located along the western border of the U.S. state of Indiana. Vigo County is included in the Terre Haute, Indiana, Metropolitan Statistical Area. The county seat is Terre Haute.
According to the 2010 census, the population was 107,848. The county contains four incorporated settlements with a total population of nearly 63,000, as well as several unincorporated communities. It is divided into twelve townships which provide local services to the residents.
The county is one of the best bellwether regions for voting in U.S. presidential elections; it has voted for the winning candidate in every election since 1956 and in all but two elections since 1892. It continued the trend in 2012, voting for President Barack Obama by only a half point margin.
Sullivan County was formed in 1817, and the area that later became Vigo County was part of it until 1818, when the county was created by an act of the Indiana General Assembly which took effect on February 1. Its borders changed several times; in 1821, part of the county was formed into Parke County, and later that year Putnam County was formed which also affected Vigo's borders. The final change came in 1873 when the present boundaries were defined. The county is named in honor of Colonel Francis Vigo, of Italian heritage but a citizen of Spain due to residence in St. Louis. He is credited with great assistance to George Rogers Clark both in financing Clark's exploration and American Revolutionary War efforts, and in service as an agent obtaining military information for Clark against British campaigns on the then frontier.