Praja Mandals were established to promote the nationalist creed among the princely states of India. The term "princely states" refers to the regions or territories that were ruled by local princely rulers or monarchs who had a degree of autonomy under British suzerainty during the British colonial period.

The reason for the establishment of Praja Mandals was to foster a sense of nationalism and promote the idea of a united, independent India among the people of these princely states. While British India was directly ruled by the British government, the princely states were semi-autonomous entities, and it was important to garner their support for the Indian independence movement.

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