The earliest traces of settlement in the Bierstadt area date to the Stone Age. However, Bierstadt was first mentioned in historical records, as "Birgidestad", in a deed of gift on March 12, 927. The town was founded by Irish monks, who named it after the Irish national saint, St. Brigid. In the 11th–12th centuries, the (now Protestant) Church of St. Nicholas was built. The church is not only the oldest existing church in Wiesbaden, but, after the Roman-era Heathens' Wall in downtown Wiesbaden, is the second oldest building of any kind in the city.