To the unity of interest thus secured by the ascendency of the burgher aristocracy, and the unquestioned leadership of Holland in all national concerns, the House of Orange added a continuity of government. If the United Provinces owed their prosperity to Holland, they owed their very existence to the House of Orange. Had it not been for the statesmanship of William the Silent they would never have won their independence, had it not been for the generalship of Maurice they would never have maintained it. Had it not been for the patriotism and moderation of both they would have lost their republicanism as soon as they had gained it. But fortunately for the Dutch republic the princes of the House of Orange preferred to exercise most of the powers of limited kingship under the guise of an elective magistracy. The head of the House of Orange combined in his person by elections, which were never questioned for seventy years, the offices of stadtholder of five provinces, of captain general and of admiral general of the republic. For the first and most critical half century in the history of the nation the supreme management of the civil, military and naval affairs of the country were in the hands of one family, not indeed by hereditary right, but by an elective custom which had grown at least strong enough to be described as an hereditary right to election. Under their wise government the prosperity of the United Provinces had grown by leaps and bounds. The destruction of the Armada in 1588 removed from the northern seas all enemies to Dutch trade. France, torn by civil and foreign war, could not man a warship or despatch a merchant fleet. England was a more serious rival, but political friendship kept for a time commercial enmities in check. The world was found large enough for both countries, and while English enterprise tended to flow in the direction of America and the West, the Dutch pursued their conquests in Africa and the East. In the East Indies alone, the famous Spice Islands of romance, the two nations found themselves in acute and deadly rivalry, and for some years a war raged on the other side of the globe between the servants of the two East India companies, which was only taken notice of by the home governments when some serious breach of international rights, such as the massacre of Amboyna, forced them to open their eyes and lazily demand compensation. [Sidenote: =Prosperity of the Dutch, 1600–1650.=]