Battle of Bouvines
Engelbert was excommunicated by Pope Innocent III in 1206, on account of his support for his cousin Adolf of Altena, archbishop of Cologne, in the interests of Philip of Swabia against Otto of Brunswick but was pardoned in 1208. In 1212, as an act of penance for his earlier rebellion, he took part in the Albigensian Crusade. He gave his allegiance to the future Frederick II, Holy Roman Emperor, after the Battle of Bouvines in 1214.