The Illinois Open 2007: Spite of the Long Knives

Winston Churchill and Douglas Haig were both present at this battle, in which the Maxim machine gun proved the decisive edge for British troops over the Ansar commanded by the Khalifa Abdullah al-Taashi, and following which, the winning commander continued onward to Fashoda. For ten points, identify this 1898 battle which saw the victory of ... ................
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