The parish of Merthyr Tydfil was governed by a local board from 1850 until 1894, when it was replaced by an urban district council.

The independents managed to form the council's administration on the mayor's casting vote.

[2] The first election to the council following the Local Government Act 1972 was held in 1973, initially operating as a shadow authority before coming into its revised powers on 1 April 1974.

Political control of the council since 1974 has been held by the following parties:[7] Lower-tier borough County borough The leaders of the council since 2005 have been:[8] Following the 2022 election, and subsequent by-elections and changes of allegiance up to September 2024, the composition of the council was: Twelve of the independent councillors sit together as the 'Independent Group', two form the 'Pant Community Independents' and the other two are not aligned to a group.

In 1989 a new civic centre was built on Castle Street, which opened as the council's headquarters at the start of January 1990.