My brain is claiming there is such a word, but Google seems to disagree:
Is there any word with the same "flavor" as
hence (somewhat ostentatious, perhaps? Victorian?) in the meaning of "in the future", but with the opposite meaning. I want to say something happened two decades hence (meaning two decades ago), but I know it's wrong (it would actually mean two decades from now).
heretofore and perhaps
yet, which have the "flavor" I'm seeking and the generally opposite meaning, but they don't seem to have the same idea of "number of years or amount of time" before now that
hence allows for...
 It would fit into a sentence similar to or along these lines:
"Born forty-eight years [hence?], the gentleman accomplished several feats of note"
Is there such a word?