Calenberg was a castle east of the River Leine; its ruins are by the village of Altcalenberg, a little to the north of Nordstemmen and lying south of Hanover. The Calenberger Land runs northwestwards from the castle, mostly to the west of the River Leine and between that river and the Deister hills.
The northern section came to Brunswick from the Counts of Roden in 1248 and became part of the share of Brunswick-Lüneburg in 1267; the south came from the Counts of Hallermund in 1282 as mortgaged land. In the partition of the Brunswick lands in 1428 the district formed part of the lands of the Middle House of Brunswick. In 1432 the two brothers partitioned their lands, the elder becoming Duke of Brunswick-Calenberg. The lands of Wolfenbüttel and Calenberg reunited in 1473 but were divided again in 1495, Calenberg being held, together with Göttingen, by the younger brother and his male descendants until they died out in 1584, when the lands reverted to the Duke of Wolfenbüttel.
After the death of the last Duke of that line in 1634, a redistribution of lands made Calenberg and Göttingen the share of the heir to Brunswick-Celle. Between 1636 and 1692 the Duchy of Calenberg was held by Duke George and four of his sons in succession, though George and two of the four sons did not live to succeed to the senior Duchy of Celle.
Previous Dukes had resided in various places besides the castle at Calenberg. George, who died in 1641, made his residence at Hanover and the Duchy was often called Hanover in consequence. His fourth son, Ernest Augustus, Duke of Calenberg after the death of his brother in 1679, was raised in status to be Elector of HANOVER in 1692. Ernest Augustus’s son, George Louis, united all the Brunswick-Lüneburg lands in 1705.