After his father's death in 1437, Jan I and his brother
Nicholas I inherited the Duchy of
Opole as co-rulers. On 6 October 1438 Jan paid homage to
Casimir Jagiełło as King-elect of
Bohemia, but after his resignation and the coronation of
Albert of Habsburg as King, he paid homage again, this time to the Austrian ruler (this was performed officially in
Wrocław on 3 December 1438). Jan I died on 5 September 1439 and the place of his burial is unknown. Because he never married or had children, all the Duchy was inherited by his brother Nicholas I.