sry but whoever said "an" is "an" idiot ;-)
opp,, what an impolite comment :'(
"History" comes from the Greek, ἱστορία. The "h" sound is the result of an accent, a vocal affectation, rather than anything etymological. English uses "an" with words that start with vowels, as "history" does in its roots. It's like "an hour." The reason that we use "a" with words like "house" and "hatred" is that these words come from Germanic or other similar roots.