In Bihar there has been a good deal of mixture among the various castes. Though Brahmans and Kshatriyas belong to the same racial stock, the Kshatriyas are more mixed because of their marriage with various stocks of people. The lower castes like the Koiri, Kurmi, Kahar and Ahir represent various racial strains. Caste rivalries and prejudices are numerous in Bihar. The narrow-mindedness of the people is one of the chief causes of the unsatisfactory state of Bihar politics. But now though modern life, better education and above all the efforts of its enlightened youth, are gradually doing away with the prejudices.
Brahman, Bhumihar, Rajput, Banias and Kayastha are the dominant castes. Kayasthas and Banias are the two important caste groups in the cities and towns. The Kayasthas are prominent in all modern professional occupations and are generally given the status of elite castes. The Banias predominate in trade and commerce. Bhumihars are regarded as a caste different from the Brahmans who consider the former inferior in the social hierarchy. Members of all these caste groups have occupied prominent positions in the educational and political life of the state.
The other land owning castes are Ahirs (Yadavas), Kurmis and Koiris in the plains of Bihar. The Ahirs or Yadavas are agricultural caste. Cattle-raising is their hereditary occupation most are settled cultivators. Some still roam about selling milk and ghee. Koiris are agriculturists. They are distinguished from Kurmis and other purely cultivating castes by their skill in growing vegetables and other special cash crops. In the neighbourhood of large towns they work as market-gardeners. Many Koiris are rich land owners. Some of them are still prosperous cultivators, holding occupancy rights.
The most notable among the schedule castes are Bhumij, Chamar (Mochi), Dhobi, Dom, Dusadh, Musahar, Nat and Pasi. Their means of livelihood still being hard manual and menial. About 92 percent of the total population of these castes are confined to the village while those in the towns and cities are slum-dwellers who work on pavements. Although education is free for them, the vast majority of them still continue to wallow in illiteracy.
The Musahars are field labours whose wages are paid in cash or in kind according to the traditional custom in the villages. Most of them live apart from the basti. Only a few have attained the dignity of cultivating on their own account. Another caste, Dusadhs are probably of aboriginal descent. A large number of them serves as watchmen or chaukidars, they are also employed as village messengers, grooms, elephant drivers and wood cutters, punkha coolies and porters.
The Dhanuks are servant class found in every place where there are high caste Hindus. The poor among them perform the menial household duties along with their family. Some Dhanuks are also cultivators while the females act as maid servants.
Insane prejudice which was prevalent against the lower castes is gradually disappearing in Bihar. The rich titled classes in the state are regarded as ordinary mortals. In the country districts the influence of Zamindar (land lords) families is considerable. It depends more on their position as landlords than as persons of title. In small towns they have a certain importance on account of their historic descent. In the larger towns the members of the upper classes are of small account unless accompanied by wealth.
The middle classes in Bihar are mostly caste-ridden. They are mostly professionals and doesn't have caste prejudices. They are the ones who almost monopolize the bar, the bench, the medical profession, trade and industry, the civil service and educational appointments. Many important posts in the secretariat are held by men of humble birth. The middle classes merge imperceptibly into the lower middle class and then into the masses.