This study brings together the expertise of an international group of scholars to survey the development of political and economic relations between Britain and the Netherlands from the Napoleonic era to the present day. It illuminates both the underlying refrain of harmony in international outlook, ideology and interests that often made for close co-operation between the two countries, and also their episodic instances of conflict. The contributors address topics ranging from Anglo-Dutch relations in the era of imperialism; the tensions created by Dutch neutrality in the First World; the challenges of the inter-war years; the role of the Dutch in British strategy during the Second World War; colonialism and decolonisation; and, most recently, bilateral relations in the European framework. Based on detailed research in British and Dutch archives, Unspoken Allies provides new insights into relations between two of the principal 'amphibious' powers of Europe across the last two centuries.