And of course it's counterpart or opposite, 'often' that falls into the same Old English category.
I tried to search for both words in the Suggestions and Discussion but they are such common words that the system boggled or declined to make the effort! I even tried 'oftentimes' (does seldomtimes exist?) But I suspect although oftentimes feels obsolescent, that it is a poetic invention from the original often, presumably to aid rhyme or scansion.
Oftentimes revealed a great quotation from Grand Panjandrum Gailr (where is she now?) Here's the quote:
This is apparently a translation in 1693 of a 16th century writing by Rabelais. I wonder what is the French for oftentimes. Souventtemps? Surely not."In the vigour of his age he married Gargamelle, daughter to the King of the Parpaillons, a jolly pug, and well-mouthed wench. These two did oftentimes do the two-backed beast together, joyfully rubbing and frotting their bacon 'gainst one another."