Dr. Patrick Hunt, Stanford University, speaks. Hannibal, a Carthaginian commander who lived ca. 200 BCE, is considered one of the greatest military commanders in history. His use of the environment in his warfare against Rome in the Second Punic War—often called the Hannibalic War—set precedents in military history, utilizing nature and weather conditions as weapons to complement his generally smaller forces. This strategic marshaling of nature could be described as a “second, secret army,” as demonstrated in his battles at Trebbia, Trasimene, and Cannae.