Complex sentence: As most of the previous crew had deserted, Fry recruited a new crew of 52 men, both American and British; many whom were inexperienced and apparently did not understand that "Virginius" was supporting the Cuban rebellion.
Split into simpler sentences: As most of the previous crew had deserted, Fry recruited a new crew of 52 men, both American and British. Many were inexperienced and apparently did not understand that "Virginius" was supporting the Cuban rebellion.