He became Chief of the Imperial General Staff and was closely involved in the reorganisation of the British Army in the early years of the 20th century.

[1] Nicholson graduated from Leeds Grammar School in 1863 and entered the Royal Military Academy, Woolwich, where he was awarded the Pollock Medal the following year.

[2] His force made a successful flanking movement at the battle of Tel-el-Kebir[2] and opened up the way to Cairo by cutting the enemy's railway system near Zagazig, where Nicholson, then with the cavalry, captured four trains under steam, which were later used to transport British infantry.

[2] Service in the Third Anglo-Burmese War, which stamped out the guerrilla activities that followed the overthrow of King Thibaw Min, earned Nicholson a further mention in despatches[8] and promotion to the rank of brevet lieutenant colonel on 1 July 1887.

[9] Nicholson was appointed Military Secretary to Lord Roberts, Commander-in-Chief in India on 1 July 1890[10] and granted the substantive rank of colonel on 1 January 1891.

[15] He was again appointed as Military Secretary to Lord Roberts, now Commander-in-Chief in South Africa, on 23 December 1899 during the Second Boer War,[16] and was granted the local rank of major-general.

[20] Nicholson returned to London in late December 1900,[21] was appointed Director-General of Mobilisation and Military Intelligence at Headquarters on 1 May 1901[22] and was promoted to lieutenant general on 4 November 1901.

[33] As CIGS Nicholson was closely involved in the reorganisation of the British Army, consolidating the Territorial Force and the creation of a modern general staff.

[34] Nicholson had a sharp tongue and one occasion Admiral Fisher asked Maurice Hankey to stop "Old Nick" "stamping his hoof on his toes".

[35] At the Committee of Imperial Defence meeting after the Agadir Crisis the First Sea Lord Admiral Arthur Wilson said that in the event of war the Navy planned to land the Army on the Baltic Coast.

[36] From autumn 1914, shortly after the outbreak of the First World War, he served on the Committee of Imperial Defence, investigating the conduct of operations in Gallipoli and Mesopotamia and in 1916 he was appointed to the Dardanelles Commission.