Salah ad-Din, Yusuf ibn Ayyub
Alexander the Great
Sir Arthur Wellesley, Duke of Wellington
Akbar the Great
I voted for Alexander the Great but my first choice would probably be Flavius Belisarius, who with little real support from his emperor Justinian, won a number of major compaigns and reconquered much of the lost Western Roman Empire.
Quo usque tandem abutere, Trump, patientia nostra?