The Peninsular War continues to be of great interest to students of military history, but the various siege operations have tended to be overlooked. However as Frederick Myatt demonstrates in British Sieges of the Peninsular War, they are of no less interest than the battles in the open fields, particularly in Spain where the circumstances were so unusual. The British Army under Wellington was hopelessly outnumbered by the French and could only keep the field at all by virtue of the superior supply system which enabled them to remain concentrated, whereas the French, who lived off the country, were compelled to disperse widely in order to survive. They were nevertheless capable of rapid concentration for a particular object, so that any siege operation conducted by the British inevitably ran the risk of being overwhelmed by sheer weight of numbers of the relieving force. As a result, Wellington's main preoccupation was not how long it would take to bring a siege to a successful conclusion by normal means but rather what chance he had of snatching success before the French overcame their supply problems and arrived in front of him.