Complex sentence: With Milan in Imperial hands, Francis personally led a French army into Lombardy in 1525, only to be defeated and captured at the battle of Pavia; imprisoned in Madrid, Francis was forced to agree to extensive concessions over his Italian territories.
Split into simpler sentences: With Milan in Imperial hands, Francis personally led a French army into Lombardy in 1525, only to be defeated and captured at the battle of Pavia. Imprisoned in Madrid, Francis was forced to agree to extensive concessions of his Italian territories.