Duke Amadeus IX of Savoy, born in 1435, was a significant figure in the House of Savoy. He became Duke in 1465 and is known for his efforts to strengthen the duchy through diplomacy and military campaigns. His reign was marked by attempts to expand the territory and influence of the Savoy dynasty in northern Italy. Amadeus IX was also recognized for his piety and support of the Catholic Church. He was beatified in 1677, reflecting his reputation for holiness and charitable works. His legacy includes contributions to the cultural and political landscape of Savoy during the late 15th century.