Founded 1263 by John de Balliol. Sister College -– St John’s College Cambridge. Men and Women – Undergraduates 387 Postgraduates 327. Balliol is one of the oldest and largest of the colleges in Oxford with around 327 postgraduates and 387 undergraduates. It has recently become the most popular, with more applications than any other in the university. Balliol is situated right in the heart of the city on its original site with a lease dating back to foundation year – 1263. A student coup in the 1960’s