Kurmi is a traditionally non-elite tiller caste in the lower Gangetic plain of India, especially southern regions of Awadh, eastern Uttar Pradesh and parts of Bihar and Jharkhand. The Kurmi came to be known for their exceptional work ethic, superior tillage and manuring, and gender-neutral culture, bringing praise from Mughal and British administrators alike.

There are several late-19th century theories of the etymology of Kurmi. According to Jogendra Nath Bhattacharya (1896), the word may be derived from an Indian tribal language, or be a Sanskrit compound term krishi karmi, "agriculturalist." A theory of Gustav Salomon Oppert (1893) holds that it may be derived from kṛṣmi, meaning "ploughman".

According to Suniti Kumar Chatterji (1926), the Bengali word kuṛmī or kurmī derives from Sanskrit kuṭumbin. This view is endorsed in Ralph Lilley Turner's A Comparative Dictionary of the Indo-Aryan Languages (1962–1985), where he lists cognates across many Indo-Aryan languages including Bhojpuri, Bihari, and Eastern Hindi.

With the continued waning of Mughal Empire rule in the early 18th century, the Indian subcontinent's hinterland dwellers, many of whom were armed and nomadic, began to appear more frequently in settled areas and interact with townspeople and agriculturists. Many new rulers of the 18th century came from such nomadic backgrounds. The effect of this interaction on India's social organisation lasted well into the colonial period. During much of this time, non-elite tillers and pastoralists, such as the Kurmi, were part of a social spectrum that blended only indistinctly into the elite landowning classes at one end, and the menial or ritually polluting classes at the other.

The Kurmi were famed as market gardeners. In western and northern Awadh, for example, for much of the 18th century, the Muslim gentry offered the Kurmi highly discounted rental rates for clearing the jungle and cultivating it. Once the land had been brought stably under the plough, however, the land rent was usually raised to 30 to 80 per cent above the going rate. Although British revenue officials later ascribed the high rent to the prejudice among the elite rural castes against handling the plough, the main reason was the greater productivity of the Kurmi, whose success lay in superior manuring. According to historian Christopher Bayly,

Whereas the majority of cultivators manured only the lands immediately around the village and used these lands for growing food grains, Kurmis avoided using animal dung for fuel and manured the poorer lands farther from the village (the manjha). They were able, therefore, to grow valuable market crops such as potatoes, melons and tobacco immediately around the village, sow fine grains in the manjha, and restrict the poor millet subsistence crops to the periphery. A network of ganjs (fixed rural markets) and Kurmi or Kacchi settlements could transform a local economy within a year or two.

Cross-cultural influences were felt also. Hindu tillers worshipped at Muslim shrines in the small towns founded by their Muslim overlords. The Hindu Kurmis of Chunar and Jaunpur, for instance, took up the Muslim custom of marrying first cousins and of burying their dead. In some regions, the Kurmis' success as tillers led to land ownership, and to avowals of high status, as noted, for examples, by Francis Buchanan in the early 19th century among the Ayodhya Kurmis of the Awadh. Earlier, in the late eighteenth century, when Asaf-Ud-Dowlah, the fourth Nawab of Awadh, attempted to grant the kshatriya title of Raja to a group of influential landed Ayodhya Kurmis, he was thwarted by a united opposition of Rajputs, who were themselves (as described by Buchanan), "a group of newcomers to the court, who had been peasant soldiers only a few years before ..." According to historian William Pinch:

Rajputs of Awadh, who along with brahmans constituted the main beneficiaries of what historian Richard Barnett characterizes as "Asaf's permissive program of social mobility," were not willing to let that mobility reach beyond certain arbitrary socio-cultural boundaries. ... The divergent claims to status in the nineteenth century (and earlier) illustrate the point that for non-Muslims, while varna was generally accepted as the basis for identity, on the whole little agreement prevailed with respect to the place of the individual and the jati within a varna hierarchy.