Page "Gondor" Paragraph 4

The territory that would become Gondor had been widely colonised by the Númenóreans from around the middle of the Second Age, especially by the Elf-friends loyal to the house of Elendil.

When his sons Isildur and Anárion landed in Middle-earth after the drowning of Númenor, they were welcomed by the colonists and their claim of lordship was accepted, while Elendil was held to be the High King of all lands of the Dúnedain.

Within the South-kingdom, the hometowns of Isildur and Anárion were Minas Ithil and Minas Anor respectively, and the capital city Osgiliath was situated between them.