Lavant (in Latin Lavantina) was a bishopric suffragan of the Prince-archbishop of Salzburg, then in the southern part of imperial Austria's Styria. Later the area was reassigned to presentday Slovenia. It became the Slovenian bishopric of Maribor, a suffragan of the Archbishop of Ljubljana, on 5 March 1962. On 7 April 2006 the diocese was elevated to the Archdiocese of Maribor.
While the bishops of Lavant bore the title of prince (Fürst), this was purely honorary and they never became full-fledged prince-bishops with secular power over an independent prince-bishopric (Hochstift) such as the Prince-Bishops of Passau or Freising or the Prince-Archbishops of Salzburg. They only exercised pastoral authority over their diocese like other ordinary bishops and for that reason, they did not have seat and voice in the Imperial Diet.(Wikipedia)