Complex sentence: He appears as Master of the Jedi High Council and one of the last members of the order's upper echelons before the Galactic Republic's fall, he is the Council's primary liaison but the Clone Wars caused him to question his most firmly held beliefs.
Split into simpler sentences: He appears as Master of the Jedi High Council and one of the last members of the order's upper echelons before the Galactic Republic's fall. The Clone Wars caused him to question his most firmly held beliefs.