In 1855, William M. Allen donated land to establish a new community in St. Charles County, laid out the town as a narrow tract seven blocks long running east and west, and established a train station to serve the local community. He donated land and money for construction of the railroad and persuaded area farmers to do the same. The first train arrived in 1857, and construction of the railroad line was under the direction of Erasmus L. Wentz, a principal engineer for the St. Louis, Kansas City and North Missouri Railroad. The presence of the railroad allowed the community to get local agricultural products to other areas between 1850 and 1880, when the area was primarily engaged in growing tobacco. Wentz assisted Allen in surveying the town lots and streets, and the settlers and Allen held him in such high esteem that they named the town after him. The City of Wentzville was incorporated as a fourth-class city in March 1872.