Shogun was commonly used by the Westerners, as well as the romaji in some cases. But strictly speaking, one should not refer shogun... but as seii taishogun. I don't know the official translation, but the title means something like "Worthey general, supressor of the barbarians". Barbarian, at the time of the first shogun, were the ones that were not yet conquered and assimilated by the central power of Japan, such as Ainu people.
I am pretty sure that the title is granted by the Emperor, since Japanese leaders usually use Emperor as an excuse to portray themselves and honorable and rightful leader chosen by righteous Emperor rubbish... but I am not 100% sure whether the seii taishoguns gave himself such title or not. My Japanese history knowledge is fading as I am learning more about Western history. If you find the answer to this, please let me know. I need to remember this...
Edited by pekau - 19-May-2007 at 13:51