Genghis (call me Temujin) Khan.
Ho Chi Min
Alexander (third of his name in the line of Macedon) the Great
Julius (call me Gaius) Caesar
Napoleon (di Buonaparte) Bonaparte and Hannibal (son of Hamilcar) Barca (honorable mentions)
IMO, to earn the title of GOAT military commander, you have to demonstrate tactical wizardry, strategic genius, and beloved, visionary leadership. Oh, and you have to win in the end.
I can think of tactical wizards like Guderian, Jackson, Lee, Leonidas, Patton, and Rommel. These are the guys that understand maneuver and terrain and win battles. But they either missed the big strategic picture or never got a chance to make those kinds of decisions.
I can think of strategic geniuses like Eisenhower, Grant, Ivar the Boneless, MacArthur, Themistocles, and Zhukov. These are the guys that understand supply and logistics (theirs and the enemy’s) and how to flex national power to win wars. But their battlefield record is either less impressive than the first group or not well known to us.
Many in both these groups were beloved by their men and/or visionary leaders.
But only Genghis, Min, Alex, and Caesar demonstrate all three attributes. All four showed their tactical wizardry in specific battles and/or in the revolutionary tactics their forces put on display. All four were strategic geniuses who understood the relative strengths and weaknesses of their nations and enemies in depth and employed them accordingly to win wars. And all four were much loved by their men and had visionary foresight in where they wanted to take themselves and their people.
Napoleon and Hannibal get honorable mentions. They also displayed all three attributes. But they ultimately did not win.
Lastly, I’ll note that Genghis, Min, Alex, Caesar, and Napoleon had both military and political control. That’s not true of most of the other names I’ve mentioned. That may be a necessary condition to make the accomplishments required to be considered a GOAT military commander, at least as I’ve defined it.
Most Land conquered? Alexander the great and Hannibal.
Apologies for being nitpicky, but that title goes to Genghis.