The English Civil War (1642-1651) was a series of armed conflicts and political machinations between Parliamentarians ('Roundheads') and Royalists ('Cavaliers'), fundamentally over governance and authority, leading to the temporary overthrow of the monarchy and the establishment of a Commonwealth under Oliver Cromwell. The war fundamentally shaped the future of the British monarchy and parliamentary democracy, highlighting issues such as the balance of power, individual rights, and religious freedoms.