While stationed in Piatra Neamț during the interwar, Coroamă took up various political and cultural activities, overseeing the Romanian Scouts and setting up a Military Club. He was also involved in establishing a local branch of the Iron Guard. He was moved around to the garrison in Satu Mare, also becoming a General in 1934. Despite his commitment to the revolutionary ideology of the Guard, he was well-liked by King Carol II, and in 1937 became commander of the Royal Palace garrison. This allowed him to sabotage Carol's attempt to use Palace troops against the Guard, and helped in toppling Carol. In the aftermath of the coup, Coroamă was mistrusted and marginalized by "Conducător" Ion Antonescu. Given command of the 4th Army Corps in Iași, he witnessed the clashes between Antonescu and his Guard colleagues, peaking during the Legionary Rebellion of 1941. Coroamă took a moderate stance, and his mediation helped Antonescu to restore order in Iași without bloodshed. However, Coroamă remained isolated by government, and had to resign. Later in 1941, as Nazi Germany and Romania opened an Eastern Front against the Soviet Union, Coroamă advised against continuing the offensive beyond Bessarabia. When this was ignored, he left military life altogether.