The Canadian Cavalry Brigade at first included the Royal Canadian Dragoons, Lord Strathcona's Horse (Royal Canadians) and the 2nd King Edward's Horse, the latter being a British yeomanry regiment made up largely of colonial personnel recruited in England. As the war dragged on and casualties mounted, there were not enough "colonials" in England to fill the ranks, and so the King Edwards were replaced by the Fort Garry Horse. The CCB thus became all-Canadian, for all practical purposes--except for their brigadier.
Besides fighting the Germans, Galloper Jack Seely had to fend off the Canadian government, which was not taking kindly to an Imperial officer commanding the Brigade; and those in government and the British army who saw no place in modern warfare for cavalry.
In early 1918, events overtook theory. Seely was in England, struggling to stave off Canadian political opposition to his leadership, when the Germans launched Operation Michael, driving British and French forces back along a front that stretched some sixty-five kilometres. Galloper Jack struggled to physically get back to the Continent to lead his troops. Lead them he did, into the--for them and him--cataclysmic Battle of Moreuil Wood. In that battle Lieutenant Gordon Flowerdew earned his posthumous Victoria Cross, and the Canadian Cavalry Brigade suffered their worst day of the war, while turning back the German thrust.
Brigadier-general Seely was replaced by a Canadian officer shortly after, but not before he had lived through what he later felt was the high point of his career, if not his life--commanding the Canadian Cavalry Brigade.