All the great cities of Holland and Zealand drove out their garrisons. The northern Provinces of Gelderland, Overyssel, and Friesland, followed their example, and by the summer half of the Low Countries were in revolt. [Sidenote: The massacre of St. Bartholomew.] A yet greater danger threatened Alva in the south, where Mons had been surprised by Lewis of Nassau, and where the Calvinists were crying for support from the Huguenots of France. The opening which their rising afforded was seized by the Huguenot leaders as a political engine to break the power which Catharine of Medicis exercised over Charles the Ninth, and to set aside her policy of religious balance by placing France at the head of Protestantism in the West. Weak and passionate in temper, jealous of the warlike fame which his brother, the Duke of Anjou, had won at Montcontour, dreading above all the power of Spain and eager to grasp the opportunity of breaking it by a seizure of the Netherlands, Charles listened to the counsels of Coligni, who pressed for war upon Philip and promised the support of the Huguenots in an invasion of the Low Countries. Never had a fairer prospect opened to French ambition. But Catharine had no mind to be set aside. To her cool political temper the supremacy of the Huguenots seemed as fatal to the Crown as the supremacy of the Catholics. A triumph of Calvinism in the Netherlands, wrought out by the swords of the French Calvinists, would decide not only the religious but the political destinies of France; and Catharine saw ruin for the monarchy in a France at once Protestant and free. She suddenly united with the Guises and suffered them to rouse the fanatical mob of Paris, while she won back the king by picturing the royal power as about to pass into the hands of Coligni. On the twenty-fourth of August, St. Bartholomew's day, the plot broke out in an awful massacre. At Paris the populace murdered Coligni and almost all the Huguenot leaders. A hundred thousand Protestants fell as the fury spread from town to town. In that awful hour Philip and Catholicism were saved. The Spanish king laughed for joy. The new Pope, Gregory the Thirteenth, ordered a _Te Deum_ to be sung. Instead of conquering the Netherlands France plunged madly back into a chaos of civil war, and the Low Countries were left to cope single-handed with the armies of Spain. [Sidenote: Elizabeth and the Netherlands.]