 He was knighted in 1914, and advanced to Knight Commander of the Order of St Michael and St George (KCMG) in 1919; he was also made a Companion of the Order of the Bath (CB) in 1915.At the outbreak of the First World War, Herringham was a lieutenant-colonel in command of the medical unit of the London University OTC.Between 1914 and 1919, he was consultant physician to the British Forces in France in the Royal Army Medical Corps, initially as a Colonel and rising to the rank of Major-General in 1918., Herringham was already sufficiently well known that his army appointment was reported in the New York Times under the headline "Famous Doctors to Front".