For the administrative purpose, the district Chandauli was constituted in the year 1997 from the district Varanasi. The district is situated in the eastern and southern side of holy river Ganga. The district is named after its tahsil headquarters name. The region covered by the present district was part of the ancient kingdom of kashi. Apart from the numerous legends connected with this district, valuable evidence of antiquity has been found here and the remains of brick strewn mounds are spread all over the district.
The history of the district for the most part is unknown. There are some deserted sites, tanks and kund seen in tahsils of the district and they carry vague legends. One of the ancient site of the district, ”Baluwa” is situated about 21 km. to the southern part of tahsil sakaldiha at the banks of river Ganga where Ganga flows from east to west direction. A religious fair for Hindus takes place every year in the month of magha(January) which is known as “Pachchim vahini Mela” it is said that the Ganga flows east to west direction only at two places in the country first in Allahabad and second one at Baluwa.Village Ramgarh of tahsil sakaldiha, known as birth place of great Aghoreshwari saint shree Kinaram Baba is just 6 km. away from Chahniya. He was a great follower of vaishnav faith and also Shiva and Shakta faith, and believed in god power. He devoted his entire life for the services of mankind. This place has become holy place for Hinduism.
In one of the ancient sites in the village Hetampur of the district, there is a fort which is known as “Fort of Hetam” which is situated about 22 km. to the north east from the district headquarters. The ruins of this fort are spread over on 22 bigas in area. It is said that this fort was designed and constructed between 14th to 15th centuries by Todar Mal Khatri who was the construction supervisor in the kingdom of Sher Shah Suri. After Mughal period, Hetam Khan, Talukedar and Jagirdar captured this fort. There are five famous ruined kot, known as Bhulaini Kot, Bhitari Kot, Bichali Kot, Uttrai Kot and Dakchhani Kot, which attract the visitors. Some says that it was constructed by Hetam himself.
Being the part of Kashi Kingdom , the history of the Chandauli district is the same as of Kashi Kingdom and of Varanasi district. Before the birth of lord Buddha, in 6th centaury B.C.,Bharatvarsha was divided into sixteen Mahajanpadas, kashi was one of them and its capital was Varanasi. Modern Banaras with its surroundings region was called as kashi Mahajanpad. Varanasi city is one of the ancient cities of India, as well as among the ancient towns of the world. It is a centre of learning since long back. It’s name comes in Puranas, Mahabharata and Ramayana. It is a centre of learning since long back. it is a sacred place of Hindu as well as Buddhist and Jain also. The name of Kashi came to be known after name of king Kashi the seventh king of this dynasty. After the seventh generation a famous King Dhanwantri, ruled over this region, whose name is famous in the field of medicine as founder of Ayurveda.
Kashi kingdom was, however, dominated by Brahmadutta dynasty of Magadh during the century preceding the Mahabharata war but past Mahabharata period saw the rise of Brahmadutta dynasty. About hundred kings of this generation are said to have had their supremacy over this region, some of these rulers become the Chakravarty Samrat. King Manoj of kashi brought the kingdom of Kaushala, Anga and Magadh in his possession and annexed their territories to his empire. In the Jain scriptures, a king of kashi named Ashwasewa was the father of 23rd Tirthankar Parshvanath.
In, 1775 Kashi Kingdom had come under the influence of British Empire. The last king of this generation was Bibhuti Narayan Singh who ruled for about eight years till the emergence of independence, Banaras state was merged with India.