Complex sentence: Carlos de Grand Pré was recalled to Havana in 1809, when Bonaparte trying to install his brother on the Spanish throne, and he was tried and executed, according to his friend Pedro Favrot for "pro-French" activities.
Split into simpler sentences: Carlos de Grand Pré was recalled to Havana in 1809, when Bonaparte was attempting to install his brother on the Spanish throne. He was tried and executed, according to his friend Pedro Favrot, for "pro-French" activities.