It was erected as a diocese in 1772 by the empress Catherine the Great, in a unilateral action independent of Rome. Its see city was the imperial capital Saint Petersburg. In 1782 Catherine elevated the diocese to an archdiocese, and in 1783 these actions were recognised by Pope Pius VI in the bull Onerosa pastoralis officii. The archdiocese remained the 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.
Mahilyow is a city in present-day Belarus, and with the demise of the Soviet Union the Archdiocese was merged with the former suffragan Diocese of Minsk, to create a new Archdiocese of Minsk-Mohilev in 1991. The territorial boundaries of the new archdiocese were redrawn to include only territory within Belarus. Territories of the former archdiocese falling within present-day Russia were reassigned, first to the Apostolic Administration of European Russia, and subsequently to what is now the Archdiocese of Mother of God at Moscow.