He served as Archbishop of Le Mans from 1918 until his death, and was elevated to the cardinalate in 1953 by Pope Pius XII.

He received his episcopal consecration on the following 17 April from Cardinal Louis-Ernest Dubois, with Bishops Claude Bardel and Joseph Guérard serving as co-consecrators.

[1] Pope Pius XII created him Cardinal Priest of S. Bernardo alle Terme in the consistory of 12 January 1953.

Despite speculation that his poor health would prevent him from participating,[2] Grente was one of the cardinal electors in the 1958 papal conclave, which selected Pope John XXIII [citation needed].

He was subject to an attack by the Canard Enchaîné on his ownership of brothels near the cathedral purchased unsuccessfully (given opposition by civil and military authorities) in view of their closure, renewed by Jean Egen in 1973.