In the middle of the sixteenth century the Baltic was thus surrounded by three independent kingdoms-Denmark-Norway, Sweden-Finland and Poland-Lithuania; a number of secular principalities owing allegiance to the Holy Roman Empire-the duchies of Holstein, Mecklenburg and Pomerania and the lands of the Livonian Order; ecclesiastical territories in Livonia headed by the archbishopric of Riga; and surrounding the Sea in an arc from east to south-west, self-governing towns and cities, most of them members of the Hanseatic League-Narva, Reval, Riga, Elbing (Elblg), Danzig, Stralsund, Lübeck and Wismar.