Astolfus of Mainz was a Benedictine monk who served as the Roman Catholic Archbishop of Mainz from 813 until 825. Born around 750, he was likely of Lombard descent and studied under his predecessor, Lul. During his tenure, he maintained significant ties with the monastery at Fulda and supported various religious institutions, including the monasteries of Bleidenstadt and Hersfeld. He is remembered for his role in consecrating several important religious sites and for his influence on contemporary clerical literature.