Complex sentence: The Polish-Lithuanian forces were commanded officially by Andrzej Firlej, but as noted by Polish historian Widacki, Firlej had little authority, and often listened to Wiśniowiecki's advice, who can be seen as the real commander of the Polish-Lithuanian forces.
Split into simpler sentences: The Polish-Lithuanian forces were commanded officially by Andrzej Firlej. However, as noted by Polish historian Widacki, Firlej had little authority, and often listened to Wiśniowiecki's advice, who could be seen as the real commander of the Polish-Lithuanian forces.