Father Andreas Amrhein (1844–1927) numbers among the many unconventional pioneers in the history of religious orders. In 1884/85, he founded the two Congregations of the Missionary Benedictines: the Congregation of St. Ottilien and the Congregation of Tutzing and directed their development at an astonishing pace. Both congregations had a considerable impact on the history of the Benedictine Order and to some extent on missionary history. The present biography attempts to document the founding history of the two congregations and to give insights into the complex character of their founder and his legacy.