He held the mayorship of Saint-Dizier until his resignation in 2017, but continued to serve in its municipal council, to which he was first elected in 1989, being reelected in 2020.

[3] From the 2017 election, he served as one of the eleven deputy chairpersons of The Republicans' parliamentary group, under the leadership of chairman Christian Jacob.

In the 2022 legislative election, he was defeated by National Rally candidate Laurence Robert-Dehault, earning 48.3% of the second-round vote.

[2] In The Republicans' 2016 presidential primaries, Cornut-Gentille endorsed Alain Juppé as the party's candidate for President of France.

[6] Ahead of the 2022 presidential election, he publicly declared his support for Michel Barnier as the party's candidate at the 2021 The Republicans congress.