During this period, he also attended the University of Salamanca, receiving a licentiate in theology on July 24, 1576.

He then did further studies in Rome, where he received a licentiate in canon law from the Angelicum.

From 1994 to 1996, he attended The Catholic University of America, receiving a licentiate in canon law.

He was educated at the Roman Seminary where he received a licentiate in theology on 3 September 1860.

He continued his studies, receiving a licentiate in utroque iure (both civil and canon law) on 15 July 1864.

He received a licentiate in theology from the Salesian University in Rome.

He received a licentiate in theology from Woodstock College in 1960.

He received a licentiate in theology in 1963.

He then attended the University of Cracow, where he received a licentiate in theology.

After receiving a licentiate in law, Longueil became a protonotary apostolic.