The Dhai Ghar (also written as Dhaighar) Khatris originally consisted of three family groups of North India – Kapoor, Khanna and Malhotra. All of these communities have been urban communities unlike other communities like Jats and Rajputs that have been largely rural communities of India. They were regarded as Kshatriyas of two and a half houses because a grouping of three is considered unlucky. They were also regarded as Khatri, especially after their expansion into Char Ghar (four houses). Mughal Emperor Aurangzeb dismissed many Khatris from the Mughul military and administrative roles since they refused the remarriage of widows of Khatri soldiers. As a result, Dhai Ghar Khatris adopted trading, business and other urban professions that many other Khatris were already engaged in and from where they frequently took wives for their sons, while giving their daughters only to the other Dhai Ghar Khatris in marriage.
Beginning in the nineteenth century, the community has progressively relaxed somewhat restrictions for marriage and modern Dhai Ghar Khatris marry at times across other communities.
There is a story that the grouping was formed by the families of three administrators - Kapur Chand, Khan Chand and Mehar Chand who had come to work in Akbar’s court from Multan. But this story appears to be a fictional one since the Mehra, Khanna and Kapoor clans have pre-existed in India as a Kshatriya clan. Historically one of the Ratna's in Mughal Emperor Akbar's Nine-Ratnas was a Khanna known as Todar Mal Khanna It is more likely that the grouping was formed in Akbar’s time for marriages from three existing kshatriya family groups - the Kapoors, Khannas and Mehras that preexisted in India. They were later expanded to form the char ghar khatris (Khatris of four houses) by including the Tandon clan or the Seth clan. The basis for the grouping appears to be suryavanshi roots rather than any other consideration. It is for this reason that the group included other suryavanshi clans that they encountered in the regions they came to inhabit such as the Tandons and the Seths. These groupings were based on the belief that all of these clans are descendents of ancient suryavanshi kshatriya clans,. The name Mehra appears to be derived from Mihira or Mihir which means Sun. Some members of the Mehra family also adopt the alternative family names of Malhotra, Mehlotra or Mehrotra.
To protect their lineage the dhai ghar khatris traditionally did not permit their daughters to marry with other khatris outside the dhai ghar. However when necessity demanded they took daughters of other khatris in marriage for their sons. The group has expanded rapidly since the time of Akbar and spread across entire North India.
The Mehra family may have migrated from a village near Nainital in Uttarakhand where an ancient village by the name of Mehra Village exists that was established by the Rajput and other kshatriya migrations into Kumaon  later returning to the plains to serve in the army of Emperor Akbar along with Rajputs from other parts of India. Modern DNA studies may throw more light on the origins of this and other family groupings of India.
In modern times the Dhai Ghar community is engaged in diverse professions in India ranging from administration to the army.
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