Complex sentence: On the other hand, the middle class enjoyed of benefits that were allowing them to prosper and was loyal to Árbenz, while the peasant were for the first time since the Rafael Carrera government in a position in which they were treated with respect and dignity.
Split into simpler sentences: On the other hand, the middle class enjoyed benefits that allowed them to prosper and they were loyal to Árbenz. The peasants were for the first time since the Rafael Carrera government treated with respect and dignity.