Question: what is the biggest military campaign in history?
Answer: Khalid ibn Walid. ...  Frederick the Great. ...  Conquest of Gaul. (58 BC) by Caesar. March across the Alps. (218 BC) by Hannibal. Defeat of Persia. (334 BC – 329 BC) by Alexander. Mongol Invasion of China. (1218 – 79) Defeat of the Third Coalition. (1805) by Napoleon. Fall of France. 1940.