My professor of modern history said it when we were on the subject of Napoleon.
Recently it was in QI as well (http://en.wikipedia.org/wiki/QI_%28G_series%29):

"Despite all the claims, many of the world's greatest dictators weren't short, and there is no proof that shorter people are more power-hungry than taller people, otherwise known as the Napoleon complex. Napoleon was above the average height at 5'7". The reason many think he was short was because the British cartoonist James Gillray. His most famous depiction of Napoleon was a picture of him standing on George III's hand in a sort of Gulliver's Travels sort of way. He was actually 3 inches taller than Nelson. Stalin was 5'5", Mussolini was 5'6", Franco was 5'4", Hitler was 5'8". Some exceptions include Idi Amin who was 6'4", the same height as Stephen, Fidel Castro was 6'1" and Mao was 5'9", which exceptionally tall for a Chinese person."