The Italian term barista (bartender) entered the English language in 1992 and its usage has considerably increased since then according to Google Books:
"bartender in a coffee shop," as a purely English word in use by 1992, from Italian, where it is said to derive ultimately from English bar (n.2), as borrowed into Italian. The word is of generic gender and may be applied with equal accuracy to women and men (it is said that the typical barista in Italy is a man).
(Etymonline)
What happened in 1992 that suddenly gave rise to the usage of the term barista? Coffee shops existed well before 1992. Was it originally an AmE or a BrE usage?