Complex sentence: Hugo of Tübingen (died 1182) had married the last heiress of the Counts of Bregenz, Elisabeth; about 1200 their son Hugo called himself a "Count of Montfort".
Split into simpler sentences: Hugo of Tübingen (died 1182) had married the last heiress of the Counts of Bregenz, named Elisabeth. Around 1200, their son Hugo called himself a "Count of Montfort".