Short answers, pulled from the story.
Hannibal was a Carthaginian general and statesman, also called Hannibal the Great, who commanded Carthage against the Roman Republic in the Second Punic War. He lived from 247 BC until between 183 and 181 BC. He is considered one of the greatest military tacticians of Western antiquity, alongside Alexander the Great and Pyrrhus.
Hannibal crossed the Alps to invade Italy by land and open a northern front against Rome rather than attacking the city directly. He set out from New Carthage in late spring of 218 BC and reached the Rhone by September with 38 elephants, almost none of which survived the harsh conditions of the Alps.
The Battle of Cannae was fought in 216 BC in the Apulian plain, where Hannibal used a double envelopment to surround and destroy a much larger Roman army. Estimates put Roman dead or captured at 50,000 to 70,000 in a single day, including a consul, 29 of 48 military tribunes, and 80 senators. Military academies still study the tactic today.
Hannibal died by suicide, poisoning himself to avoid being handed over to the Romans after Prusias I of Bithynia agreed to surrender him. The precise year is unknown, falling between 183 and 181 BC, with Polybius giving 182 BC. His tomb stood at Libyssa on the coast of the Sea of Marmara.
Hannibal swore to his father Hamilcar Barca that he would never be a friend of Rome as long as he lived. According to tradition recorded by Polybius, Hamilcar held the nine-year-old Hannibal over a sacrificial fire and made him take the oath, which is said to have occurred at Peniscola.
As elected suffete after the Second Punic War, Hannibal reorganized state finances to eliminate corruption and recover embezzled funds so Carthage could pay its indemnity of ten thousand talents without raising taxes. To curb the oligarchs of the Hundred and Four, he made them subject to direct election and limited their term to a single year.