English Civil War
King Charles made a deal with the Irish rebels to stop the fighting in Ireland, freeing up soldiers that could fight for him. Parliament made a deal with the Scottish Covenantors, who would help them. Parliament were also helped by a talented army leader called Oliver Cromwell. He led a cavalry (horse riders) unit called the "Ironsides". The Ironsides were better organised than most cavalry units, which made them far better at fighting.