This ill-starred people played a most important part in the economic development of Europe, but they were terribly maltreated by the Christians, who held them guilty of the supreme crime of putting Christ to death. The active persecution of the Jews did not, however, become common before the thirteenth century, when they first began to be required to wear a peculiar cap, or badge, which made them easily recognized and exposed them to constant insult. Later they were sometimes shut up in a particular quarter of the city, called the Jewry. Since they were excluded from the guilds, they not unnaturally turned to the business of money-lending, which no Christian might practice. Undoubtedly their occupation had much to do in causing their unpopularity. The kings permitted them to make loans, often at a most exorbitant rate; Philip Augustus allowed them to exact forty-six per cent, but reserved the right to extort their gains from them when the royal treasury was empty. In England the usual rate was a penny a pound for each week. [Sidenote: The 'Lombards' as bankers.] In the thirteenth century the Italians--"Lombards"--began to go into a sort of banking business and greatly extended the employment of bills of exchange. They lent for nothing, but exacted damages for all delay in repayment. This appeared reasonable and right even to those who condemned ordinary interest. Capitalists, moreover, could contribute money towards an enterprise and share the profits as long as no interest was exacted. In these and other ways the obstacles offered by the prejudice against interest were much reduced, and large commercial companies came into existence, especially in Italy. [Sidenote: Tolls, duties, and other annoyances to which merchants were subjected on land.]