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Jean-Luc Mélenchon led La France Insoumise in the National Assembly from 2017 to 2021. The party, known for its left-wing policies, was founded in 2016 by Mélenchon and became a significant political force in France, gaining momentum during the 2017 presidential election. La France Insoumise, under Mélenchon's leadership, advocated for policies such as social and economic reforms, environmental sustainability, and a critique of the European Union.