The name 'Kaibartha' derives from the Sanskrit words for water ('ka') and livelihood ('varta'). They are a Hindu caste of fisherfolk and cultivators who trace their descent from the mythical fisher girl, Matwyagandha. They were amongst the earliest inhabitants of Bengal. An annual festival known as 'Jal palani' or 'net preserving' is recorded in contemporary records as happening each February. It lasted between two and seven days with 'puja' or prayer held in the Ganges on the last day.
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Source: British Library (bl.uk)