On his return to France, he studied at the Ecole Centrale des Travaux Publics, and his social education was accomplished in the salon of Pauline de Beaumont, the friend of Châteaubriand and Joubert.

Molé supported the policy of the duc de Richelieu, who in 1817 entrusted to him the direction of the Ministry of Marine, which he held until December 1818.

He was Minister of Foreign Affairs in the first cabinet of Louis Philippe's reign, and was confronted with the task of reconciling the European powers to the change of government.

After a few months in office, Molé retired, and it was not until 1836 that the fall of Thiers led to his becoming Prime Minister of a new government, in which he held the portfolio of foreign affairs.

Personal and political differences rapidly arose between Molé and his chief colleague, Guizot, and led to an open rupture in March 1837 in face of the general opposition to a grant to the duc de Nemours.

Molé, supported by Louis Philippe, held his ground against the general hostility until the beginning of 1839, when, after acrid discussions on the address, the chamber was dissolved.

He died in the family home at Château de Champlâtreux [fr][1] in Épinay (Seine-et-Oise) on 23 November 1855 and was buried in the little church of the village.