Alexander was born in London and was educated at Harrow before moving on to the Royal Military College, Sandhurst, for training as an army officer of the Irish Guards.

He rose to prominence through his service in the First World War, and continued his military career through various British campaigns across Europe and Asia during the interwar period.

[15][16] He became a permanent major on 1 August 1917,[17] and was again promoted acting lieutenant colonel,[10] this time confirmed as CO of the 2nd Battalion, Irish Guards, on 15 October.

As a temporary lieutenant-colonel,[22] he led the Baltic German Landeswehr in the Latvian War of Independence, commanding units loyal to Latvia in the successful drive to eject the Bolsheviks from Latgalia.

[25] He commanded the battalion at Constantinople (a sensitive posting in the runup to the Chanak Crisis), then Gibraltar from October 1922, then in London from April 1923 until January 1926, when he was released from that role to attend the Staff College at Camberley, England, from 1926 to 1927.

Among his many fellow students were Douglas Wimberley, who would later become a major-general and command the 51st (Highland) Division from 1941—1943, including at the Second Battle of El Alamein, who formed a high opinion of Alexander, who, despite his outstanding war record, showed little sign of being overly pleased with himself.

[24] Instead, he showed "simplicity, directness and kindness" and gained the respect of all at the college, with two notable exceptions—the future field marshals Alan Brooke and Bernard Montgomery—who did not come away with a particularly favourable impression of him.

[35][36] For his service there, and in particular for his actions in the Loe-Agra operations against the Pathans in Malakand between February and April 1935, Alexander was that year made a Companion of the Order of the Star of India and was mentioned in dispatches.

[37][38] He was mentioned once more for his service during the Second Mohmand Campaign in Northwest Frontier Province from August to October of the same year, serving under Brigadier Claude Auchinleck.

[48][40][2] Following the outbreak of the Second World War, in September 1939, Alexander brought the 1st Division to France, where it became part of the British Expeditionary Force (BEF) and served there for the next eight months.

[53] He was promoted acting lieutenant-general in July 1940,[54] and in December 1940 he was appointed to succeed Claude Auchinleck as General Officer Commanding-in-Chief (GOC-in-C) of Southern Command, which was responsible for the defence of south-west England.

[62] Alexander was promoted to Commander-in-Chief (C-in-C) of Allied Land Forces in Burma, March 1942, and ordered Slim to abandon Mandalay and retreat to India.

[65][67]After the Tunisian campaign, Alexander's command became the 15th Army Group, which became responsible (under General Eisenhower) for mounting the July 1943 Allied invasion of Sicily (codenamed Operation Husky).

Montgomery's Eighth Army found itself in a slogging match against typically skilful German opposition on the Catanian plain and on the slopes of Mount Etna.

Montgomery's Eighth Army launched Operation Baytown, crossing over into Calabria but initially facing little real opposition and slowly making its way up the Italian peninsula.

Six days later the U.S. Fifth Army (which, despite its name, included the British X Corps under Lieutenant-General Richard McCreery, under its command) under Lieutenant General Mark W. Clark landed at Salerno as part of Operation Avalanche, which, initially at least, started off well, before encountering heavy resistance and almost being thrown back into the sea.

It was not until the fourth attempt that the Winter Line was breached by the Allies, and Alexander's forces moved on to capture Rome in June 1944, thereby achieving one of the strategic goals of the Italian campaign.

However, the U.S. VI Corps, now under Major General Lucian Truscott, in the Anzio beachhead, under U.S. Fifth Army commander Clark's orders, failed to follow their original break-out plan that would have trapped the German 10th Army escaping northwards in the aftermath of the Battle of Monte Cassino, instead favouring an early and highly publicised entry into Rome two days before the Allied landings in Normandy.

[80] However, Harold Macmillan (British Minister Resident in the Mediterranean from 1942 to 1945) was impressed by Alexander's calm and style - the general conducted dinners in his mess like those at an Oxbridge high table, discussing architecture and the campaigns of Belisarius, rather than the current war.

They state that he was "unable or unwilling" to assert his will over his army commanders, and that Mark Clark, who often referred to Alexander scornfully as a "peanut" and a "feather duster", exploited this weakness.

[80] With the cessation of hostilities, Alexander was under serious consideration for appointment to the post of Chief of the Imperial General Staff, the British Army's most senior position beneath the sovereign.

On these trips, he sought to engage with Canadians through various ceremonies and events; he was keenly interested in his role as Chief Scout of Canada and, in preparation for his kicking of the opening ball in the 1946 Grey Cup final, practised frequently on the grounds of the royal and viceregal residence, Rideau Hall.

Also, in commemoration of Alexander being named the first non-aboriginal chief of the Kwakiutl tribe, he was given a totem pole on 13 July 1946; crafted by Mungo Martin, it remains on the grounds of Rideau Hall today.

In his memoirs, Costello was to admit that Alexander's behaviour had in fact been perfectly civil and could have had no bearing on a decision which had already been made to declare the Republic of Ireland.

[91] The Alexanders' relatively informal lifestyle at Rideau Hall was demonstrated when during the Canadian tour of Princess Elizabeth and her husband, the Duke of Edinburgh, the Viscount and Viscountess hosted a square dance in the palace's ballroom.

Alexander painted (creating a personal studio in the former dairy at Rideau Hall and mounting classes in art at the National Gallery of Canada[14]), partook in a number of sports (including golf, ice hockey, and rugby), and enjoyed the outdoors, particularly during Ontario and Quebec's maple syrup harvest, himself overseeing the process on Rideau Hall's grounds.

"[92] Lord Alexander gave up the office of Governor General of Canada officially on 28 January 1952 after Churchill asked him to return to London to take the post of Minister of Defence in the British government.

[94] The aging Churchill had found it increasingly difficult to cope with holding that portfolio concurrently with that of prime minister, although he still took many major decisions himself, leaving Alexander with little real power.

[95] George VI died on the night of 5–6 February and Alexander, in respect of the King's mourning, departed quietly for the United Kingdom, leaving Chief Justice of Canada Thibaudeau Rinfret as administrator of the government in his place.

[2] His funeral was held on 24 June 1969, at St. George's Chapel, in Windsor Castle, and his remains are buried in the churchyard of Ridge, near Tyttenhanger, his family's Hertfordshire home.