original: The subsequent campaigns were more or less successful, and the Imperial Exarchate was established in Ravenna to oversee Italy, though actually imperial influence was often limited.
simplifications: The subsequent campaigns were successful. The Imperial Exarchate was created in Ravenna to oversee Italy. The next campaigns were more or less successful. The Imperial Exarchate was created in Ravenna to look after Italy,  but the imperial influence was often limited. The campaigns that followed were successful. The Imperial Exarchate was created in Ravenna. Its job was to oversee Italy. The imperial influence was often limited though. The next campaigns were more or less successful. Thus, the Imperial Exarchate was established in Ravenna to oversee Italy. In reality, imperial influence was often limited. The later campaigns were fairly successful. The Imperial Exarchate was made in Ravenna to oversee Italy, but imperial influence was often not a lot. The next campaigns were successful. Imperial rule was established over Italy but imperial influence was usually weak. The later efforts were pretty much successful and the Imperial Exarchate was put in place in Ravenna to rule Italy although imperial influence was often limited. The subsequent campaigns were more or less successful. The Imperial Exarchate was established in Ravenna to oversee Italy although it's influence was often limited. And in Ravenna the Imperial Exarchate was founded to oversee Italy, but in reality royal effect  was often limited. The later campaigns were almost successful, and the Imperial Exarchate was established in Ravenna to oversee Italy, though actually imperial influence was often limited.