In the month of February, 1830, Madame Clapart obtained this promotion for her son through the influence of Madame la Dauphine, granted to the Abbe Gaudron, now rector of Saint-Pauls.
Although Oscar outwardly professed to be devoted to the Bourbons, in the depths of his heart he was a liberal.

Therefore, in the struggle of 1830, he went over to the side of the people.

This desertion, which had an importance due to the crisis in which it took place, brought him before the eyes of the public.

During the excitement of triumph in the month of August he was promoted lieutenant, received the cross of the Legion of honor, and was attached as aide-de-camp to La Fayette, who gave him the rank of captain in 1832.

When the amateur of the best of all possible republics was removed from the command of the National guard, Oscar Husson, whose devotion to the new dynasty amounted to fanaticism, was appointed major of a regiment sent to Africa at the time of the first expedition undertaken by the Prince-royal.