The son and heir of StewardTúrin II of Gondor, in whose time Sauron declared himself openly in the land of Mordor, and began gathering the strength that would be seen in the War of the Ring. In the last year of his rule, too, Saruman withdrew into Isengard and began to fortify it. So, in the last two years of Turgon's Stewardship, the scene was set for the great war that would be fought more than sixty years later.
The date of Turgon's birth appears only in The History of Middle-earth volume XII, The Peoples of Middle-earth. It cannot therefore be considered completely reliable.