Josef Franz Ceminau (January 7, 1902 - December 32, 1994), alternatively spelt Joseph Cheminau, was an East Prussian Social Democratic political leader who served as the __ Chancellor of East Prussia from 1970-1977. The only Chancellor of Jewish faith and the last Chancellor born before the annexation of East Prussia into France, Cheminau oversaw East Prussia during a contentious social period in which the economy was stagnating in the late 1960's and the republic bristled under deep divisions between the ruling German population and the near-majority of non-German peoples, in particular in the East. Cheminau, while popular, eventually was forced into a divisive leadership election that relieved him of his post after his Cabinet abruptly resigned in the wake of the 1977 Vilnius Riots. Defeated by Konrad Beck, Cheminau's defeat marked the end of a period of dominance by economically liberal, social conservatives within the SPO and gave way to the considerably more left-leaning Beck government that would dominate East Prussia until 1991. Still, the SPO under Cheminau won the 1971 and 1976 elections with the greatest margins in East Prussian electoral history and the 1971-76 government is the only East Prussian government to rule with an absolute supermajority.