Vandalia is a city in Fayette County, Illinois, United States. At the 2010 Census, the population was 7,042. Vandalia is 69 miles (111 km) northeast of St. Louis, on the Kaskaskia River. It served as the state capital of Illinois from 1819 until 1839, when the seat of state government moved to the current capital of Springfield. Vandalia was for years the western terminus of the National Road. Today, Vandalia is the county seat of Fayette County and the home of the Vandalia State House State Historic Site (1836). Vandalia was founded in 1819 as a new capital city for Illinois. The previous capital, Kaskaskia, was unsuitable because it was under the constant threat of flooding.
The townsite, located in Bond County at the time,:5 was hastily prepared for the 1820 meeting of the Illinois General Assembly. In 1821, Fayette County was created, including Vandalia.:5The history of the name Vandalia is uncertain. Different theories can be found in almost all of the books written about Vandalia over the years. In her book Vandalia: Wilderness Capital of Lincoln’s Land, Mary Burtschi tells of a conversation between one of the original surveyors of the town and a Vandalia resident. The surveyor, Colonel Greenup, explained that Van was suggested by one of the men. He recommended this as an abbreviation to the word vanguard meaning the forefront of an advancing movement.
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