Thomas I (1239–1296) was the fourth Marquess of Saluzzo from 1244 to his death. He was the son of Manfred III and Beatrice of Savoy.^[1] He succeeded his father Manfred III. He was also the grandson of Amadeus IV, Count of Savoy.^[1]

Under the reign of Thomas, Saluzzo blossomed, achieving a greatness which had eluded his ancestors. He crafted a state the borders of which remained unchanged for over two centuries. He extended the march to include Carmagnola. He was often at odds with Asti and he was a prime enemy of Charles of Anjou and his Italian pretensions. During his tenure, he made Saluzzo a free city, giving it a podestà to govern in his name. He defended his castles and roccaforti (strongholds) vigorously and built many new ones in the cities.

He married Luisa of Ceva. They had:

• Manfred IV, succeeded his father^[1]
• Alice of Saluzzo, who married Richard Fitzalan, 8th Earl of Arundel^[2]