But because of the plague in 1636 T.A. and the later wars, Calenardhon was mostly empty and very few people lived there. In 2509 T.A. the Rohirrim came south from the north, to help Gondor fight against a combined invasion of Men from the north-east and Orcs from Mordor. The Rohirrim helped Gondor win the "Battle of the Field of Celebrant" and the war. As a reward, Steward Cirion of Gondor gave the land Calenardhon to the Rohirrim. The King of the Rohirrim, Eorl the Young, swore the "Oath of Eorl": that Rohan would come and help Gondor, if it needed help in its wars. Afterwards, the people of the Rohirrim moved into their new land, which they named the "Riddermark" or just "The Mark". Gondor called the land "Rohan" (Sindarin: "Land of the Horse-lords").