1977 (I was 11) at the biggest movie theater of Reims, France. It was dubbed in french (a pretty good and memorable dub), and I'm afraid in mono (just a guess, I have no memory of that !).
At that time everything was translated in french, the movie was called La guerre des étoiles, and the logo in the movie was in french as was the text crawl. The names of the characters, of the places, even the starships were translated !