From History Today by William Whyte:
In June 1686, a small family – a clergyman, his wife, and their daughter – disembarked from a ship at the docks of Boston, Massachusetts. They had just finished a long journey of a month or more across the Atlantic, escaping from England. The clergyman, a scholarly, 60 year old named Charles Morton, was fleeing prosecution. His crime? Teaching students – or, more specifically, teaching students in north London.
From 1334 onwards, graduates of Oxford and Cambridge were required to swear an oath that they would not give lectures outside these two English universities. It was a prohibition occasioned by the secession in 1333 of men from Oxford to the little Lincolnshire town of Stamford. They were escaping the violence and chaos which often attended medieval university life – the frequent battles between students, and between students and other communities within the town – the same conditions, in fact, which had led an earlier generation of scholars to up sticks and leave Oxford for Cambridge. But their action now threatened both universities, and so the Stamford experiment had to be suppressed. The sheriff of Lincoln, the lord chancellor, even the king, Edward III, were all called into play and the result became known as the ‘Stamford Oath’; an oath which Oxford and Cambridge graduates continued to swear until 1827.