Subutai (primary military strategist of Genghis and Ögedei Khan) for sure.
He directed more than twenty campaigns in which he conquered thirty-two nations and won sixty-five pitched battles, during which he conquered or overran more territory than any other commander in history.
He gained victory by means of imaginative and sophisticated strategies and routinely coordinated movements of armies that were hundreds of kilometers away from each other. He is also remembered for devising the campaign that destroyed the armies of Hungary and Poland within two days of each other, by forces over five hundred kilometers apart.
let's get back to "generals" part of this question,
Ancient times: Alexander, Scipio Africanus, Hannibal, Attila
Medieval times: Subutai/Genghis, Tamerlane, Khalid ibn al-Walid, Yue Fei
Gunpowder: Gustav II, Selim I, Toyotomi Hideyoshi, Jan Žižka, John Churchill
Imperial: Napoleon, Sir Arthur Wellesley, Alexander Suvorov, Thomas J. Jackson, Ahmad Shah Durrani
Modern: Erwin Rommel, Erich von Manstein, Heinz Guderian, George S. Patton, Georgy Zhukov, Mustafa Kemal