There have been several church councils held in the town of Split in the early Middle Ages, and whose conclusions have significance for the whole territory of the early Croatian Kingdom.
Since 920's the Byzantine Empire was considerably weakened so Emperor Romanos I gave management over Dalmatia to the Croatian King Tomislav who needed it in order to connect the church authorities in Croatia and Dalmatia so he could easily integrate Dalmatia into his Kingdom. This transfer of powers is confirmed by the fact that the Byzantine governor of Dalmatia wasn't listed as one of the participants on the official council documents.