A trying period of fifteen years followed the battle of Waterloo. The Congress of Vienna made Holland and Belgium one kingdom under the name of the United Netherlands. But this ill-advised union failed. The Dutch King, William I, was tyrannical and tactless, and ruled entirely in the interests of Holland. Although the population of Belgium was 1,500,000 more than that of the northern states of the Netherlands, four-fifths of the army officers and by far the larger part of the government officials were Dutch. Belgians were forced to pay the public debt of Holland, and the poorer classes, under the weight of intolerable taxes, faced starvation. They had fought too long for freedom to endure subjugation. Only a little encouragement was needed to spur them on to action. The throng that was assembled in the Brussels Théâtre de la Monnaie on the evening of the 25th of August, 1830, listened for a time quietly enough to Auber's new opera of "Musette de Portici." But when the Italian tenor in a stirring solo made an appeal to his countrymen to rise against foreign tyranny, the excitement of the audience could not be controlled. Springing to their feet, they caught up the words of the refrain and sang them over and over again. They rushed from the opera house into the street, still singing, "_A mon pays je dois la vie, Il me devra la liberté!_" [Illustration: THÉÂTRE DE LA MONNAIE, BRUSSELS.] The revolution begun in this dramatic fashion continued until Belgium took its place as a nation among the European powers. The new Constitution made it one of the freest countries in the world, with representative government, freedom of the press, trial by jury, freedom of education, and complete religious tolerance. The family of Orange-Nassau was forever excluded from the throne, and Prince Leopold of Saxe-Coburg was chosen king. Although a Protestant, Leopold proved an excellent king of a Catholic country, by his wisdom and prudence tiding the nation over several political crises and firmly establishing the kingdom. While still prince, he had married Princess Charlotte, heir to the crown of Great Britain. If she had lived, he would have become Prince Consort of England, but both the Princess and her only child died the following year. After assuming the crown of Belgium, Leopold formed an alliance with France by marrying Emilie Louise, daughter of Louis Philippe.