War of Independence of 1775 - Washington was a famously bad general, terrible tactician, lost more battles than won, etc. This is only partly excused in that his army was basically bleh. It is no secret that, militarily, it was the French who won this war. But the Americans came out of the war with a sweet peace treaty in 1783 that basically gave them (almost) everything they wanted. So it was really won by American diplomats (both in Paris and London) than by anything the American military did in the field.
Washington wasn't a "great captain" to be sure but he achieved his strategic goals none the less and that was for his army to simply survive those first few years. The continental army was horribly trained, organized and outfitted at the start of the conflict and the Continental Congress did not give much support to improve it. Washington knew he had no chance in open battle with the British so he did the smart thing and avoided it whenever possible. He lost several battles early on but each time managed to live to fight another day all while improving the quality of his army and also learning from his own mistakes. Eventually (with the help of a Prussian) his army improved enough to be able to fight the British to a draw at Monmouth. Much like Eisenhower, his best asset during the events that he is remembered for was more his political skill than his tactical skill. It would be interesting to debate how things would have been different if Gates had been given command instead of Washington.