 On 10 August 1941, Jaeger was appointed Archbishop of Paderborn by Pope Pius XII.He received his episcopal consecration on the following 19 October from Archbishop Cesare Orsenigo, with Bishops Joseph Machens and Augustus Baumann serving as co-consecrators.From 1962 to 1965, Jaeger attended the Second Vatican Council, with Heribert Mühlen serving as his "peritus", or theological expert.