Frederick II reached Acre

Holy Roman Emperor Frederick II was excommunicated for frequently breaking an obligation to the pope to join the crusade. In 1227 he embarked on a crusade but was forced to abandon it due to illness but in 1228 he finally reached Acre. Culturally, Frederick was the Christian monarch most empathetic to the Muslim world, having grown up in Sicily, with a Muslim bodyguard. Despite his ex-communication by Pope Gregory IX, his diplomatic skills meant the Sixth Crusade was largely a negotiation supported by force.