QUIZ: Regicide. Who was the last British Monarch to be intentionally killed?

According to Tom Petty "It's good to be King. If just for a while..." The British Isles have seen many monarchs over the centuries. Many of whom died of natural causes. Some fell in battle.Fortunately (from a regal point of view),most British monarchs have died with their heads still attached but not all.

QUIZ: Regicide is the act of killing a monarch. Who was the last British Monarch to be intentionally killed?

1. Name of monarch

2. The year the monarch was killed

3. The killer's name and reason given