The Rastogi are a Hindu Vaishya bania caste found in North India. They are concentrated in the districts of Varanasi, Farrukhabad, Kanpur, Meerut, Ghaziabad, Moradabad, Bareillyand Lukhnow in Uttar Pradesh and also in many parts of Delhi, Kolkata, Rajasthan,Haryana.
Their name is derived from Rohtas (rohit meaning sun, aas meaning vansha). Rastogis however, claim themselves to be descendants of the mythical king Harishchandra, who had a son named Rohit from whom the name Rastogi is derived, and the caste is also sometimes known as Rohatagis. Still, another view is that they are a subgroup of the Vaishya varna, a view probably based on Nesfield's (1885) theory of the occupational basis of the caste system, as Rastogis are mostly money lenders and business men.Legendary origin
Some eleven centuries ago they established their rule in the three places, one to the south of Kashi on the banks of river Som, a second in the Punjab to the west of Indraprastha, and a third at Kannauj. Of these, the first extended their kingdom further to the southeast and retained the name of their ancestral prince Rohit in the name of their capital Rohtasgarh. The second who migrated to the Punjab named their kingdom Rohtak also after the prince Rohit, while the people who migrated to Kannauj and ruled up to the fifth century AD later became known as Rothari Rajputs.
It is said that the great sage Vishwamitra, once approached Harishchandra and informed him of a promise made by the king during the sage's dream to donate his entire kingdom. (Accounts differ on how the sage had got the promise from the king. Harishchandra was so virtuous, that he immediately made good his word and donated his entire kingdom to the sage and walked away with his wife and son.
Harishchandra, with no money in his hands, had to sell his wife and son to a Brahmin Grihastha to pay for the Dakshina. The king, his wife and son had to sustain tremendous hardships doing their respective chores. The king helped the guard cremate the dead bodies, while his wife and son were used as household helpers at the house of the Brahmin. In acute penury, she could not even pay the taxes needed to cremate him. Harishchandra did not recognise his wife and son. He asked the lady to sell her golden mangalasutra and pay the tax. It is at this instance that his wife recognises the man as her husband. The faithful wife readily gave assent.
Lord Vishnu, Indra and all Devas and the sage Vishwamitra himself manifested themselves on the scene, and praised Harishchandra for his perseverance and steadfastness. They brought his son back to life. They also offered the king and his wife, instant places in heaven. The virtuous king, refused saying that he cannot leave behind his subjects, by Kshatriya Dharma. He asked for a place in heaven for all his subjects. The gods, now immensely pleased with the unassailable character of the great king, offered heavenly abode to the king, the queen and all their subjects.
The sage Vishwamitra helped to populate the kingdom again and installed Harishchandra's son as the king.
Rohitashva - He was the son of Harishchandra. He founded town of Rohtas Garh in Rohtas district, Bihar and Rohtak, originally Rohitakaul, meaning from the Kul (family) of Rohit.