Which political parties competed for control of Uttar Pradesh after the early 1990s?

Since the early 1990s, political control in Uttar Pradesh has been characterized by a fractious landscape, with power frequently shifting between three primary political parties:1

• Bharatiya Janata Party (BJP): A major national party that has held power in the state at various times, including leading coalition governments and, more recently, forming a government under Chief Minister Yogi Adityanath.21
• Samajwadi Party (SP): Founded by Mulayam Singh Yadav in 1992, this party has formed several governments in the state (notably in 1993, 2003, and 2012) and remains a significant regional force led by Akhilesh Yadav.2
• Bahujan Samaj Party (BSP): Established to represent Dalits and other disadvantaged groups, the party became a powerful force under the leadership of Kumari Mayawati. It has held power in the state on multiple occasions, including a decisive majority victory in 2007.3

On several occasions, particularly following periods of significant civil unrest, the state has also been placed under the direct control of the national government.1