The staple trade made Boston a centre of intellectual influence from the Continent, including the teachings of John Calvin that became known as Calvinism. This, in turn, revolutionised the Christian beliefs and practices of many Bostonians and residents of the neighbouring shires of England. In 1607, a group of pilgrims from Nottinghamshire led by William Brewster and William Bradford attempted to escape pressure to conform with the teaching of the English church by going to the Netherlands from Boston. At that time, unsanctioned emigration was illegal, and they were brought before the court in the Guildhall. Most of the pilgrims were released fairly soon, and the following year, set sail for the Netherlands, settling in Leiden. In 1620, several of these were among the group who moved to New England in the "Mayflower".