Here is my list of top 8 assassinations in the early ages of mankind that had a great impact on mankind:

1. Julius Caesar was assassinated by a group of pro republicans in Ancient Rome on 44BC. The assassins were Brutus, Cassius and some other co-senators of Caesar. This assassination has a great impact on history of Rome, since it led to ultimately the nephew of Caesar to become the first single ruler of Rome.
2. Sennacherib, the king of Assyria during 7th century BC was assassinated by two of his sons in 681 BC. He was succeeded by his youngest son Esarhaddon who brought the Golden Age to Assyria.
3. Maobite king Eglon was killed by Ehud in about 1220 BC upon supposed order of God to Ehud. The death of Eglon, King of Moabites the land was peaceful for 80 years then.
4. Cain kill Abel, his brother and son of Adam, the first man on earth, by stabbing him with a sharp bone. Thus Abel became the first human to be murdered.

1. Gedaliah, a wise man and a governor of Judah, was killed in 585 BC by Yishmael, a descendant of the last king of Judah before it came under the rule of Nebuchandnezzar II or Babylon.
2. Philips II of Macedonia, father of Alexander the Great, was killed by Pausanias, one of his own bodyguards
3. Attila, the Hun, most aptly known as the scourge of Europe was assassinated by his newly wed wife Gudrun in 453 BC.
4. Holofernes , an Assyrian general was killed, according to the Old Testament, by Judith, a Hebrew widow, which resulted prevention of complete destruction of Jews.