Roman Catholic Archdiocese of Mohilev

The Archdiocese of Mohilev (or Mogilev or Mahilyow) was a territorial Latin Church ecclesiastical jurisdiction of the Catholic Church, covering the greater part of the territory of the Tsarist Russian Empire (from St Petersburg to Vladivostock). The Cathedral was the Church of the Assumption of the Virgin and St. Stanislav in Mohilev, the co-cathedral was the Cathedral of the Assumption of the Blessed Virgin Mary in Saint Petersburg. Its effective see was the imperial capital city Saint Petersburg.

Throughout its entire existence, it was the largest territorial unit of the Catholic Church in the world. The archdiocese remained the Latin metropolitan see for Russia throughout imperial times and the Soviet period, although for much of the latter period it was the subject of repression and had no incumbent archbishop.