The Solemn League and Covenant was a formal agreement made in 1643 between the Parliamentarians of England and the Scottish Covenanters. Its primary aim was to unite both nations in their efforts against the rule of King Charles I and to promote the Presbyterian form of church governance. The covenant emphasized the importance of maintaining the Protestant faith and sought to protect the rights of the church. The agreement played a significant role during the English Civil War, as it helped to solidify the alliance between the two groups. It also influenced the political landscape of Britain, leading to the eventual establishment of the Commonwealth of England under Oliver Cromwell.