Laocoon was a Trojan priest in Greek mythology, who along with his two sons, was attacked by giant snakes sent by the gods. The phrase "I fear the Greeks even bearing gifts" is attributed to him.
According to one source, he was the priest of Apollo and should have been celibate; however, he had married and had two sons. As a punishment, the god sent giant snakes that killed his sons and left him alive in order to suffer.
A different source accounts the way he died. When the Greeks offered the famous horse to the Trojans, towards the end of the Trojan War, Laocoon warned the Trojans not to accept it, but instead set it on fire to make sure it was not a trick. The goddess Athena, angry with him and the Trojans, caused an earthquake around Laocoon and blinded him. Watching this, the Trojans thought that Laocoon was being punished for torturing Sinon, the undercover Greek soldier who asked the Trojans to take the horse inside the city gates. So, they took the horse inside the city. This source says that Laocoon kept asking the Trojans to set fire to the horse, and Athena sent the giant serpents that killed him and his two sons.