The two concrete moles protecting the outer harbour at Dunkirk played a significant part in the evacuation of British and French troops during World War II in May/June 1940. The harbour had been made unusable by German bombing and it was clear that troops were not going to be taken directly off the beaches fast enough. Naval captain W. G. Tennant had been placed ashore to take charge of the navy shore parties and organise the evacuation. Tennant had what proved to be the highly successful idea of using the East Mole to take off troops. The moles had never been designed to dock ships, but despite this, the majority of troops rescued from Dunkirk were taken off in this way. James Campbell Clouston, pier master on the east mole, organised and regulated the flow of men on that site.