Sigismund Ernst Hohenwart (1745–1825) was the third bishop of Linz from 1809 to 1825.
He had been a cathedral canon of Gurk and Vicar-General of Klagenfurt. He was appointed by the emperor on 10 January 1809, but the appointment did not receive papal approbation until December, 1814, on account of the imprisonment of the pope.
This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed. (1913). "Linz". Catholic Encyclopedia. New York: Robert Appleton Company.