On other fronts, there was still room for the use of strategy of maneuver. The Germans executed a perfect battle of annihilation against the Russians at the Battle of Tannenberg. In 1915 Britain and France launched the well-intentioned but poorly conceived and ultimately fruitless Dardanelles Campaign, combining naval power and an amphibious landing, in an effort to aid their Russian ally and knock the Ottoman Empire out of the war. The Palestine campaign was dominated by cavalry, which flourished in the local terrain, and the British achieved two breakthrough victories at Gaza (1917) and Megiddo (1918). Colonel T. E. Lawrence and other British officers led Arab irregulars on a guerrilla campaign against the Ottomans, using strategy and tactics developed during the Boer Wars.