Greece hosted two substantial Allied forces in 1917 with a strength of c. 600,000. The French General, Maurice Sarrail, commanded the Allied Army of the Orient comprising French, British, Serbian, Greek and Russian brigades and Lieutenant General George Milne commanded the British Salonika Force (BSF). The government of Greece was, however, in chaos. The pro-German king’s ousting of the pro-Allied Prime Minister Venizelos had provoked a national schism that divided the country into royalist and Venizelist-held territories. Nonetheless, Sarrail resolved on a broad-based offensive in April along the Struma valley, between Lakes Ohrid and Dojran. The action was inconclusive, with the fiercest fighting around Lake Dojran; minor Allied gains were quickly reversed by vigorous Bulgarian counterattacks, and the action was called off on 21 May. The political crisis was shortly to be resolved; King Constantine abdicated on 11 June and Venizelos, back in power, took Greece into the war on the Allied side.
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