A friend and I are arguing, she claims Australia came up with 'mate' as a friendly colloquial term, I claim that England did, that it is derived from the word 'ship-mate', and that this term was shortened to 'mate' and subsequently used among sailors and pirates alike as they traveled across the globe during the Golden Age of Piracy or a similar time. Is either of us correct, or is the answer totally different?
It's difficult to trace the precise linguistic history of any word, but "mate," in that sense, most likely entered the English language in the 14th Century through Middle-Low Germanic māt, roughly meaning "person you eat with." The word in German derived from Proto-Germanic ga-māton, literally translating as "having food together."
The word "companion" entered the English language in a similar fashion around 1300, but through French (compagnon), which was in turn derived from Latin (companionem, literally "with bread").
(If it's any consolation, the association with sailors/sailing dates back to at least the 15th century.)
The online etymology dictionary gives this derivation:
mate (n.1) Look up mate at Dictionary.com"associate, fellow, comrade," mid-14c., also "companion" (late 14c.), from Middle Low German mate, gemate "one eating at the same table, messmate," from Proto-Germanic *ga-maton "having food (*matiz) together (*ga-)," which is etymologically identical with companion. Cognate with Danish and Swedish mat, German Maat "mate," Dutch maat, from German. Meaning "one of a wedded pair" is attested from 1540s. Used as a form of address by sailors, laborers, etc., since at least mid-15c. Meaning "officer on a merchant vessel is from late 15c.
Although the term originally had a non-nautical origin. It's use seems to have been preserved in nautical settings in the terms "mess-mate", and "ship-mate" and then spread back into general colloquial usage from there.
I think you are more correct than your friend about the sources of the modern term.