By profession a medical doctor, he advocated the cause of the French Revolution and was expelled by the Sardinian authorities. In 1793, he treated the French sick and wounded during the Siege of Toulon and was appointed to command a sapper battalion. He later fought in the Army of Italy and the Army of the Eastern Pyrenees before returning to Italy.
By the time of the Montenotte Campaign in 1796, he was a general officer leading major units. He was captured by the Austrians during the 1799 Italian campaign. After commanding garrisons for several years, he led a division in Italy during the 1809 war.
He was killed in action at Soissons during the War of the Sixth Coalition. Rusca is one of the names inscribed under the Arc de Triomphe.