Siragusa took over leadership of the Pittsburgh crime family after the murder of Stefano Monastero in 1929. It is believed that Siragusa was a loyal follower of the Brooklyn Castellammarese family led by Stefano Magaddino and later Salvatore Maranzano. Like many bosses in smaller cities, Siragusa made tribute payments to Maranzano who aspired to be the "Capi di Tutti Capi" of the American Mafia.