Middle-earth kingdom founded jointly in SA 3320, by Isildur and Anarion, sons of Elendil and exiles from the Downfall of Númenor.

When founded, Gondor consisted of all the lands between the River Isen and the River Harnen, all land south of Fangorn and the River Limlight, and all land east of the Anduin. It also included all lands west of Mordor, as far north as the area known as the Dagorlad. Enedwaith in Eriador was jointly administered by Gondor and Arnor.

Over the next 1100 years, the Kings of Gondor added more territories and, by TA 1050, at the height of its power, Gondor included Umbar and Enedwaith. At that time all of Haradwaith was also tributary to Gondor. Southern Rhovanion as far east as the sea of Rhun was added in TA 1248. This was the largest size Gondor achieved and it did not stay that large for long.

In TA 1448 the sons and followers of Castamir captured Umbar. They and their descendants became the Corsairs and became sworn enmies to their former homeland.

In TA 1636, the Great Plague killed off much of the population, and from then on the population in the outlying areas, especially Calenardhon in the north, and all of the lands east of the Anduin, dwindled.

In TA 1856, much of the eastern territories of Gondor were lost in battle with the Wainriders. The Wainriders were finally defeated in TA 1944 but the population of Gondor's territories east of the Anduin never recovered.

In TA 2000, an assault led by the Nazgûl captured Minas Ithil, the main city of Gondor on the Eastern side of the Anduin. From then on, although Gondor never reliqiuished its claim on them, all of the lands east of the Anduin were abandoned by all but bands of soldiers.

In TA 2510, Calenardhon was presented to the Rohirrim for their aid in the battle of the Field of Celebrant. Gondor was then reduced to the lands between the Rivers Isen and Anduin, south of the White Mountains, plus Anorien to the north of the mountains. It stayed this size until the destruction of the One Ring and the end of the War of the Ring.
Encyclopedia entry originally written by PotbellyHairyfoot