Benelux (Dutch) comes from Dutch België, from Dutch -ië, from Middle Dutch -ie, from Old French -ie, from Latin -ia, from Latin -ius, from Proto-Italic -jōs, from Proto-Indo-European -yós — Creates adjectives from noun or verb stems.
Ancestry of “Benelux”, step by step
Benelux traces back through 3 separate lines of ancestry.