Complex sentence: Even without the help of the Bourbons, Crocco, skilled in guerrilla warfare, was able to harass the Piedmontese soldiers but his force was betrayed by Giuseppe Caruso, one of his lieutenants.
Split into simpler sentences: Even without the help of the Bourbons, Crocco, skilled in guerrilla warfare, was able to harass the Piedmontese soldiers. Suddenly, Crocco was betrayed by Giuseppe Caruso, one of his lieutenants.