The history of amphibious operations in the British Isles reaches back at least as far as Julius Caesar's legions crossing the Channel to invade from Gaul. For centuries the Royal Navy had been landing soldiers on hostile shores, prominent examples being Quebec 1759, Peking 1900, Zeebrugge 1918, and Gallipoli 1915–16. During the inter-war period, however, a combination of recent experience and economic stringency contributed to the delay in procuring equipment and adopting a universal doctrine for amphibious operations.