Complex sentence: His argument was that he had already paid 300 beeves to Fitzwilliam to keep the sheriff out; nevertheless, Captain Willis was made sheriff in command of 100 men, and disaffected members of the clan were encouraged to defy him.
Split into simpler sentences: His argument was that he had already paid 300 beeves to Fitzwilliam to keep the sheriff out. Nevertheless, Captain Willis was made sheriff in command of 100 men, and disaffected members of the clan were encouraged to defy him.