Known to friends as "Bungo", Byng was born to a noble family at Wrotham Park in Hertfordshire, England and educated at Eton College, along with his brothers.

Byng proved to be popular with Canadians due to his war leadership, though his stepping directly into political affairs became the catalyst for widespread changes to the role of the Crown in all of the British Dominions.

By raising money through buying polo ponies cheaply, using his excellent horsemanship to train them, and then selling them on at a profit,[9] Byng was able to transfer to the 10th Royal Hussars on 27 January 1883,[10] and less than three months later he joined the regiment in Lucknow, India.

Most of the rebels were then dispersed shortly after, and on 29 March the regiment re-embarked for Britain, arriving on 22 April, and proceeding to their new base at Shorncliffe Army Camp in Kent.

During the summer of 1884, Byng spent much of his time playing polo and training recruits and horses, and in July, for his services in Sudan, he was mentioned in despatches.

He thus, in order to dedicate his time to preparatory studies, which continued when the regiment moved in 1891 to Ireland, resigned his commission as adjutant and turned down an invitation from Prince Albert Victor to join him in India as an equerry.

After being detached for a time in order to serve and gain more experience in the infantry and artillery,[20] Byng sat and passed his entrance exams into the Staff College and secured a nomination in September 1892.

[23] Once Byng was enrolled at the Staff College, he found amongst his fellow students men with whom he would be closely associated more than two decades later—Henry Rawlinson, Henry Hughes Wilson, Thomas D'Oyly Snow, and James Aylmer Lowthorpe Haldane—and in 1894, while en route to visit a friend at Aldershot, travelled with a cadet at the nearby Sandhurst, Winston Churchill.

[24][25] Byng also journeyed with his class to see the battlefields of the Franco-Prussian War at Alsace-Lorraine and accompanied to the United States one of his lecturers who was compiling information on a book on Stonewall Jackson.

[33][19] The beginning of 1902 brought more significant events for Byng, with his return to England in March,[34] an audience with King Edward VII the following month,[35] at which he was appointed to the Royal Victorian Order as a member 4th class (MVO),[36] and his marriage to Moreton at St Paul's Church, Knightsbridge, on 30 April 1902.

[50] In October 1912 Byng became general officer commanding (GOC) British Troops in Egypt,[51][52] where he remained until the outbreak of the First World War in the summer of 1914.

Kitchener, then on leave on England and soon to become Secretary of State for War, recalled Byng back to Britain to become GOC of the newly created 3rd Cavalry Division.

[53][54] This he did in late September,[55] and, with his division, soon departed for the Western Front, landing at Ostend on 8 October, to reinforce the British Expeditionary Force (BEF).

[62][63] By May, he found himself in command of the Canadian Corps–"which was generally regarded, not least by those in it, as one of the crack formations on the Western Front"–and was promoted when, for distinguished service, the King made substantive Byng's rank of lieutenant-general.

[66]Byng's greatest glory then came when he led the Canadian victory in April 1917 at the battle of Vimy Ridge, a historic military milestone for the dominion that inspired nationalism at home.

[76] The Germans launched their spring offensive on 21 March 1918, which continued over the following weeks and managed to inflict heavy losses on Byng's Third Army, although it was able to retreat without breaking his line.

Byng's Third Army launched an attack on the Germans on 21 August, where, on 27 September, it managed to break through the Hindenburg Line before continuing on to Maubeuge, which was reached on 10 November, the day before the Armistice with Germany.

[83] The designation proved less controversial than his predecessor, the Duke of Devonshire, due partly to the General's popularity, but also because the practice of prior consultation with the Canadian prime minister, at that time Arthur Meighen, was revived.

[85] He was also fond of the Royal Agricultural Winter Fair, held each year in Toronto, and established the Governor General's Cup to be presented at the competition.

In the summer of 1926 he denied the recommendation of his prime minister, William Lyon Mackenzie King, who sought to have parliament dissolved in order to avoid a vote of non-confidence in his government.

[87] At the 1926 Imperial Conference, King then went on to use Byng and his refusal to follow his prime minister's advice as the impetus for widespread constitutional change throughout the British Commonwealth.