The term
shogun, meaning "great general' is a contraction of
seiitaishogun, meaning "the great general who overcomes the savages". Originally it was a title given to military commanders of princely rank for the duration of a campaign. However, after it had been awarded to Minamoto Yoritomo it became a hereditary title in the Minamoto lineage, indicating the
de facto ruler of
Japan, even while the emperor remained the
de jure ruler.