This fourth collection of Dr Luttrell’s studies on the military order of the Hospital concerns its activities on the island of Rhodes, acquired between 1306 and 1310, where it struggled to contain the naval aggression of the Anatolian Turks and to settle the island and organise its society and economy. At the same time it had to exploit its Cypriot possessions and its European provinces in order to secure the manpower and resources needed to sustain its Eastern activities. The author has spent over 40 years working in the Hospital’s archives on Malta and elsewhere throughout the West, studying the Hospitallers’ military and naval affairs, their spiritual and medical activities, and the organisation of their Western priories and commanderies. These studies illustrate the workings of an extensive multi-national corporation dedicated to the defence of Christendom.