Kathmandu Valley
Historically, the valley and adjoining areas made up a confederation known as the Nepal Mandala. Until the 15th century, Khwopa was its capital, when two other capitals, Kathmandu and Yala, were established. After the annexation of the valley by the Gorkha Kingdom, and subsequent conversion of the Valley as the capital of their empire, the designation of "Nepal" was extended to all the lands they had conquered.