Turnover isn't rare in the bar industry, but the interviewer still needs to ask, to ensure that you haven't burned any bridges or been fired for stealing. Share why you chose to leave while only talking positively about your co-workers and the establishment where you last worked.
You may state that you needed to submit your resignation because your next semester school schedule would not align with their needs. Or, you may say that the establishment closed their doors. Be sure to mention something that you really liked about the job, and share that you are excited to get back to bartending.
"My last position was great - I liked it. Unfortunately, they were purchased by a larger restaurant group, and our whole team was laid off. This is why I am seeking a new opportunity."
"I just graduated from bartending school and look forward to my first bartending gig! This position is a dream opportunity for me."
"I worked as a bartender at a nightclub for the past four years. I left because the atmosphere was no longer healthy for me. I am now seeking an opportunity where I can work in a more relaxed environment with regular customers and potentially an older crowd. Your pub is an establishment that I regularly come to on my days off, so I know it is much more my vibe."