The campaign reflected the British desire to reverse the defeats of the Mahdist War in the 1880s, as well as concern that France and other European powers would take advantage of Sudan's instability to acquire parts of its territory. Initially only the Egyptian Army was engaged. British Army units joined from early 1898, with two British brigades being present at the decisive victory at Omdurman on 2 September 1898, in which Winston Churchill took part. Seventeen members of the Royal Navy and 27 Royal Marines who helped man the Nile gunboats also received the medal.