1914
At the outbreak of the First World War in August 1914, Snow commanded the 4th Division, initially deployed for home defence on the east coast with its headquarters in Suffolk. "Although Snow had written Eastern Command's Defence Scheme years earlier as a staff officer, he recalled that very few people knew, or cared, that such a scheme existed and the chaos on the East Coast was appalling".
When the division arrived at the front (25 August) Snow's orders were to help prepare a defensive position on the Cambrai-Le Cateau position, as General Headquarters (GHQ) had no idea of the seriousness of the situation facing II Corps (this being at a time when I and II Corps were retreating on opposite sides of the Forest of Mormal, and the British Expeditionary Force's Chief of Staff, Archibald Murray, was about to collapse from strain and overwork). Snow was in time to take part in the Battle of Le Cateau. The 4th Division covered the left flank of II Corps and he was one of those who urged Smith-Dorrien to stand and fight. The diary of Lieutenant-General Horace Smith-Dorrien, the GOC of II Corps, recorded:
I learned in the course of the morning that the 4th Division (General Snow, now Lieutenant-General Sir Thomas D'Oyly Snow) had reached Le Cateau from England, and was delighted to hear that the Chief [that is, Field Marshal Sir John French, commanding the BEF] had immediately pushed it out to Solesmes, about seven miles north-west of Le Cateau, to cover the retirement of the Cavalry and 3rd Division.
Snow's division retired after the battle but GHQ and the French were left with an exaggerated impression of the losses suffered at Le Cateau. Henry Hughes Wilson, BEF Sub Chief of Staff, issued the infamous "sauve qui peut" order (27 August), (addressed from "Henry to Snowball") ordering Snow to dump unnecessary ammunition and officers' kits so that tired and wounded soldiers could be carried. Smith-Dorrien was later rebuked by Field Marshal French for countermanding the order. Snow later wrote "the retreat of 1914 was not, as is now imagined, a great military achievement, but rather a badly bungled affair only prevented from being a disaster of the first magnitude by the grit displayed by the officers and the men".
Brigadier-General Aylmer Haldane, who commanded the 10th Brigade under Snow in 1914, was highly critical of him, although he also thought many other officers of the division not up to the standards of competence required in war. By September 1914 three out of four battalion COs had been "sent home" and Snow was lucky to retain his command. Snow later revisited some places from the Great Retreat from Mons with Haldane, who recorded in his diary on 10 November 1917: "Though he is an old friend of mine I have never felt the same towards him since that time ... when he showed what a poor spirited man he was when troublous times were upon us".
In September, during the First Battle of the Marne, Snow was hospitalised, badly injured with a cracked pelvis, after his horse fell and rolled on him. In November, after partially recovering (he required further treatment for the rest of the war), he took command of the 27th Division, then being raised at Winchester for deployment to the front at the end of the year. The division consisted of regulars returning from overseas.
