Complex sentence: The Comminges was originally part of Gascony, but in 836 García I Galíndez, Count of Aragon, was made Viscount of Comminges and Viscount of Couserans.
Split into simpler sentences: The Comminges was originally part of Gascony. In 836 García I Galíndez, Count of Aragon, was made Viscount of Comminges and Viscount of Couserans.