Complex sentence: Following the Castellammarese War, Carfano became a lieutenant to Adonis and Costello and, after Charles "Lucky" Luciano's imprisonment in 1936, Carfano was named as Underboss as Costello assumed leadership of the Luciano crime family.
Split into simpler sentences: Following the Castellammarese War, Carfano became a lieutenant to Adonis and Costello. After Charles "Lucky" Luciano's imprisonment in 1936, Carfano became underboss as Costello assumed leadership of the Luciano crime family.