The Holy See established the Apostolic Prefecture of Texas on October 24, 1839, with Odin assigned as Vice-Prefect Apostolic under Rev. John Timon. He there labored among Catholics, many of whom had fallen away amid the disorders accompanying the change of government, as well as non-Catholics and Native Americans. He was later named Coadjutor Bishop of Detroit, Michigan, in December 1840 but declined the appointment in May 1841.