Joffre, as we have seen, had been replaced by Nivelle. Lloyd George did not quite dare do the same with Haig, but in a devious intrigue he subordinated him to French command—a manœuvre from which relations between British military and civilian leadership never recovered. Nivelle’s own optimism was not shared by his fellow-generals.
His political support was undermined by the overthrow of the French Premier Aristide Briand, whose successors had little confidence in Nivelle’s military plans. When on 16 April Nivelle launched his much-heralded offensive across the Aisne against the wooded heights of the Chemin des Dames, it was under the worst possible auspices. The Germans had received ample advance warning French plans had been disrupted by the German withdrawal to the Hindenburg line; and the weather was terrible. Instead of the promised breakthrough, there was a painful advance of a few miles that had to be called off after ten days, by which time the French had suffered over 130,000 casualties.
Nivelle was replaced by Pétain, the hero of Verdun, but by now the French army had had enough. It collapsed, not so much into mutiny as into the equivalent of a civil strike, whole units refusing to obey orders and return to the front. Pétain gradually nursed it back to health with a minimum of severity, largely by improving its conditions and refraining from any major offensive actions, but the French army on the Western Front could make little further contribution for the remainder of the year.
The British did better—at least to begin with. A week before the opening of the French offensive across the Aisne they had attacked further east, at Arras. The first phase of the operation succeeded brilliantly, with Canadian troops seizing the dominating Vimy Ridge. Haig again hoped for a breakthrough, but the new German defences baffled him. The British offensive once more gradually slowed down until it was broken off at the end of May with a loss of a further 130,000 men. But there could be no question in Haig’s mind of suspending his attacks. By this time not only the French, but also the Russians, were hors de combat; no effective help would be forthcoming from the United States for another year; and, worst of all, the German submarine campaign seemed to be succeeding. As a wag put it at the time, ‘The question is, whether the British Army can win the war before the Navy loses it.’