[Sidenote: Lord North changes front, and France interferes, Feb., 1778.] This capture of a British army made more ado in Europe than anything which had happened for many a day. It was compared to Leuktra and the Caudine Fork. The immediate effect in England was to weaken the king and cause Lord North to change his policy. The tea-duty and the obnoxious acts of 1774 were repealed, the principles of colonial independence of Parliament laid down by Otis and Henry were admitted, and commissioners were sent over to America to negotiate terms of peace. It was hoped that by such ample concessions the Americans might be so appeased as to be willing to adopt some arrangement which would leave their country a part of the British Empire. As soon as the French government saw the first symptoms of such a change of policy on the part of Lord North, it decided to enter into an alliance with the United States. There was much sympathy for the Americans among educated people of all grades of society in France; but the action of the government was determined purely by hatred of England. While Great Britain and her colonies were weakening each other by war, France had up to this moment not cared to interfere. But if there was the slightest chance of a reconciliation, it was high time to prevent it; and besides, the American cause was now prosperous, and something might be made of it. The moment had come for France to seek revenge for the disasters of the Seven Years' War; and on the 6th of February, 1778, her treaty of alliance with the United States was signed at Paris. [Sidenote: Untimely death of Lord Chatham, May 11, 1778.]