Auxvasse is a city in northern Callaway County, Missouri, United States. It is part of the Jefferson City, Missouri Metropolitan Statistical Area. Th…Auxvasse is a city in northern Callaway County, Missouri, United States. It is part of the Jefferson City, Missouri Metropolitan Statistical Area. The population was 983 at the 2010 census. Auxvasse was originally called Clinton City, and under the latter name was platted in 1873 named after the nearby Auxvasse Creek. A post office called Auxvasse has been in operation since 1874. Auxvasse has been claimed by at least 3 Callaway County townships since they were first delineated in 1821, when Auxvasse was located at the far northeast corner of the original boundaries of the then far-larger Cote Sans Dessein township for a period of only a few months. New townships were formed 1821–1838 in northern Callaway County, and a study of historical references should clarify which township Auxvasse was claimed by during that period. In February 1838, the newly formed Liberty Township included Auxvasse as a key town in its eastern sector for nearly 40 years; but when the newer Jackson Township was created in December 1875, Auxvasse was included instead in its western half, where it remains to this day as its largest population center.