 During Frederick's first invasion of northern Italy, Henry took part, among the others, in the victorious sieges of Crema and Milan.In 1172, Henry took a pilgrimage to Jerusalem (June–July), meeting with the Knights Templar and Knights Hospitaller, and spending Easter of that year in Constantinople.By December 1172, he was back in Bavaria and in 1174, he refused to aid Frederick in a renewed invasion of Lombardy because he was preoccupied with securing his own borders in the East.