My husband's "Brust" first shows up in the 1860 Wisconsin Federal Census, Sheboygan County, as Mary Brust, aged about 84, born in Prussia about 1786. She is living with Benjamin Fricke and his wife Johane Louise Fricke--possible maiden name Brust? Do you have any other info on your Mary Brust. Fondulac County is right next to Sheboygan County. Possibly a connection? Look forward to hearing from you.