Complex sentence: Liutward's men abducted the daughter of Unroch III of Friuli from a convent in Brescia and forced her to marry one of his relatives, this provoked enmity between Liutward, the chief Carolingian prelate in Lombardy, and Berengar of Friuli, the chief secular magnate.
Split into simpler sentences: Liutward's men abducted the daughter of Unroch III of Friuli from a convent in Brescia and forced her to marry one of his relatives. This provoked enmity between Liutward, the chief Carolingian prelate in Lombardy, and Berengar of Friuli, the chief secular magnate.