These commercial problems of Baltic timber imports were compounded by a military and strategic problem. The dependency on Baltic timber was paramount in the minds of British statesmen in the late seventeenth century mostly because of the strategic dangers. There were no trades as militarily important as the Baltic lumber trade, but there were also few more fragile. Besides the trade coming from Norway, the timber ships had to come through the Sound – the narrow straits separating Denmark from Sweden- a passage easily blocked by enemy navies, especially the Dutch who were geographically well placed to impede trade through the North Sea, as could, to a lesser extent, the French. Also threatening was the rise of Sweden who by 1690 was at the height of its brief period of being a global power. Sweden also was a strong trade protectionist and had imposed high duties of British imports. Sweden's empire was also expanding having seized Livonia as well as Pomerania, both important sources of timber. Thus beginning with the Anglo-Dutch wars of the later seventeenth century British statesmen and merchants began to look for some alternative to these imports.