Ranchi district is the most populous district of Jharkhand state in eastern India. Ranchi, the capital of Jharkhand, is the district headquarters. It was established as a district in 1899. History of Ranchi district Iron slag, potsherds and iron tools have been found in the Chota Nagpur plateau dated to 1400 BCE. Magadha Empire exercised indirect control over the territory, which lasted until the reign of the Ashoka. Kalinga rulers are believed to have ravaged the region during their expeditions to Rajgir and Pataliputra. Armies of Samudra Gupta passed through the region on their expedition to Deccan. After the decline of the Guptas, Phani Mukut Rai established the Nagvanshi dynasty c. 1000 CE, which ruled Ranchi district and part of Chota Nagpur Plateau as a sovereign king for almost next 1000 years. Khukhragarh was one of the capitals of Nagvanshi dynasty. With the expansion of the Mughal Empire, the Nagvanshis were forced to pay tribute, but they continued to rule and administer independently until the advent of the East India Company. Thakur Vishwanath Shahdeo, Pandey Ganpat Rai, Tikait Umrao Singh and Sheikh Bhikhari played pivotal role in Indian Rebellion of 1857. During the period of the British Raj, Adivasis and other locals of the Chotanagpur Plateau continued to oppose the subjugation by the British, and the region witnessed a number of uprisings and revolts. Ranchi has a humid subtropical climate. However, due to its position and the forests around the city, it is known for its pleasant climate. Its climate is the primary reason why Ranchi was once the summer capital of the undivided State of Bihar. Ranchi used to be a preferable hill station in the past. Temperature ranges from maximum 42 to 20 °C during summer, and from 25 to 0 °C during winter. December and January are the coolest months with temperature getting to freezing point in some places of the city. The annual rainfall is about 1430 mm (56.34 inches). From June to September the rainfall is about 1,100 mm. Ranchi is located at 23°21′N 85°20′E.