Quote from : Fractured Emerald: Ireland Book

There had been a time, until 1422, when a number of both Gaelic and Anglo-Irish students attended Oxford and Cambridge in England. But fellow students had complained that Irish living together in large numbers sooner or later got noisy and violent and there was no handling them. Accordingly, the universities imposed a quota system on Irishman, and decreed that those admitted must be scattered around among non-compatriots: exclusively Irish halls of residence were banned.