[acheron]

Feet and inches long predate imperial units, and the US has never used the imperial system, btw. “Imperial” has a specific meaning and isn’t just “anything not metric”.

Anyway, base 12 is also built into most Germanic languages which have unique names for 11 and 12 (rather than something along the lines of “one-teen” and “two-teen”, which is more common in Romance languages IIRC.

[debugnik]

Out of the most spoken romance languages, Spanish and Portuguese have distinct names up to 15, French and Italian up to 16, while Romanian does stop at 10. This suggests hexadecimal influence to me.