The Prince-Bishopric of Ratzeburg (German: Fürstbistum Ratzeburg) was an ecclesiastical principality of the Holy Roman Empire that was located in what is today the states of Schleswig-Holstein (the district of Herzogtum Lauenburg) and Mecklenburg-Vorpommern (the district of Nordwestmecklenburg) in Germany. It was established in 1236 and disestablished following the Peace of Westphalia in 1648. The state capital was the city of Ratzeburg. The Diocese of Ratzeburg had originally been established as a diocese of the Catholic Church in the 11th century but had fallen into abeyance; as a result of the Wendish Crusade, the diocese was re-created in the middle of the 12th century. The territory of the prince-bishopric was managed by secular lords on behalf of the Bishop of Ratzeburg. As a Prince-