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Maharashtra is the state in India where Bal Thackeray's Shiv Sena is primarily active. The party, founded by Thackeray in 1966, is known for its strong regionalist ideology and its promotion of Marathi culture and language. Shiv Sena has a significant presence in Maharashtra, particularly in the state capital, Mumbai, and is known for its active participation in local politics and its influence in shaping regional policies and developments.