Complex sentence: Soon the whole of Aquitaine was submitting to Charles the Bald, and in 852, Pippin II was made prisoner by the Basques and handed over to his uncle Charles the Bald who put him in a monastery.
Split into simpler sentences: Soon the whole of Aquitaine was submitting to Charles the Bald. In 852, Pippin II was taken prisoner by the Basques and handed over to his uncle Charles the Bald who put him in a monastery.