While what David said is true, "See the Conquering hero Comes" is from Handel's oratorio "Judas Maccabeus" which has its own, much older story. Google Judas Maccabeus for all that as well as all the ways in which the tune has been used. We only ever learned "Conquering Hero" at school (a very long time ago!) and it was years later that I heard it, much to my surprise, as "Thine be the Glory".

(I play a snatch of it for the entry, and resurrection, of our gallant hero during our Mummer's play! Now wondering how many people think I'm playing " Conquering Hero" or "Thine be the Glory"! I suppose either fits the chracter, and some won't know the tune anyway.)