Ruling Steward
From Tolkien Gateway
The title used of the rulers of Gondor after the loss of the last King, Eärnur. The first of the Ruling Stewards was Mardil Voronwë, and the title was carried in line of succession through twenty-six generations to Denethor II, Ruling Steward at the time of the War of the Ring. His son Faramir gave the rule of Gondor to Aragorn, the rightful Heir of Isildur.