Engelbert I (died 1 April 1096 in Saint Paul's Abbey, Lavanttal) was Margrave of Istria (1090–1096), Count of Sponheim, Kraichgau, and Pustertal and Vogt of the Archbishopric of Salzburg. As a supporter of Pope Gregory VII during the Investiture Controversy, he lost the county of Pustertal. In 1091, Engelbert founded the Benedictine monastery of St. Paul. He retired as a monk there in 1095 and died in 1096.