This book marks the first comprehensive examination of contemporary British influence in Oman and Bahrain, analysing Britain’s legacy since the official withdrawal from the Gulf in 1971. Using theories of power as a framework, the book examines the development of British economic, strategic, and political influence in the two countries post-withdrawal, a topic overlooked by academics and political observers. The author argues that a divergence has developed between Britain’s influence in Oman (a site of strategic power) and Bahrain (a site of economic power). Focusing on the British Government, private corporations, and individuals, topics range from the development of British Foreign Direct Investments and the presence of British oil and gas companies in the region to joint defence training exercises and the presence of Omani and Bahraini military cadets in British military academies. The book also crucially assesses the increasing influence that the Gulf states are gaining over Britain as the legacy of the Residency gradually fades. British Diplomacy in Oman and Bahrain will be useful to students and scholars studying politics and economics in the Gulf and Britain, as well as policy analysts, international relations experts, and historians interested in the legacy of colonialism.