Regicide is a term used to describe the deliberate killing of a king by one of his subjects. It has particular resonance within the concept of the Divine Right of Kings, whereby monarchs were presumed by decision of God to have a divinely anointed authority to rule. As such, an attack on a king by one of his own subjects was taken to amount a direct challenge to (i) the monarch, (ii) his Divine Right to Rule, and (iii) God's will. Even after the disappearance of the Divine Right of Kings and the appearance of Constitutional Monarchies, the term continued and continues to be used to describe the murder of a king by one of his subjects or citizens.
Five famous historical regicides were the executions or deliberate assassinations of
- Henry IV of France in 1610 assassinated by Ravaillac;
- Charles I of England in 1649 after sentence of death by parliament;
- Louis XVI of France in 1793, after sentence of death by parliament;
- Umberto I of Italy in 1900 by an assassin;
- ex-Tsar Nicholas II of Russia in 1918 by some of his former subjects.