A civil war is when two groups of people in the same country find it impossible to agree without violence. Most countries have had a civil war. The English Civil War was between the supporters of King Charles I and Parliament (Cavaliers and Roundheads). The American Civil War was between the peoples who wanted to end slavery (the northerners or yankees) and those in the south who felt they were losing control of their own right to govern as they pleased.

Civil wars are not that different to revolutions. A revolution is when a group of people overthrow a government. Sometimes it results in war, such as the American War of Independence, but often it does not, such as the French Revolution.