Brusilov was born in Tiflis (now Tbilisi, Georgia). His father was Russian, his mother, Anna Luiza Niestojemska, was Polish. Three generations of Brusilov's had served as officers in the Tsar's army, his grandfather fighting in the defense against Napoleon's invasion of 1812. His father rose to the rank of Lieutenant General before dying of tuberculosis in 1856. Brusilov's mother died shortly afterwards, and the young orphan was raised by relatives in Kutaisi.

He was educated at home until at the age of 14, he joined the Imperial Corps of Pages in Saint Petersburg in 1867. At the end of his first year, a tutor remarked of Brusilov, "his nature is brisk and even playful, but he is good, straight - forward and clean - living. Of high ability, but inclined to be lazy." The description of the youth would still be true of the general, fifty years later (except, it would seem, on the issue of laziness).

In 1872, on completion of the Corps' program, he sought admission to the advanced class for top ranking students, but was unsuccessful, and instead was posted as an ensign to the 15th (Tver) Dragoon Regiment. Usually, graduates from the Corps of Pages sought admission to one of the Guards regiments, but the Tver Dragoons were at that time stationed near Kutaisi, so the posting suited Brusilov on the basis of being near his family and being less financially draining than service in the Guards.

Brusilov joined the Tver Dragoons in August, 1872, and was given command of a troop, but it was not long before his aptitude resulted in appointment as regimental adjutant. He was promoted to lieutenant in 1874.

Brusilov served with distinction in the Russo – Turkish War, 1877 – 78, being mentioned in despatches on three occasions. His unit operated on the Southern Front in the Caucasus, and took part in the assault of the fortress of Ardagan (now Ardahan, Turkey), for which Brusilov was awarded the Order of Saint Stanislav, 3rd Class. Later in the war, he also received the Order of Saint Anne, 3rd Class, and was promoted to the rank of Stabskapitän. Towards the end of the war, he led successful attacks on Turkish positions around Kars, and his membership of the Order of Saint Stanislav was elevated to 2nd Class.

In 1881, Brusilov became a student at the Cavalry Officer School in St Petersburg and two years later was appointed as a riding instructor there. He spent the next thirteen years in a succession of posts at the school - Adjutant, Senior Teacher of Riding and Breaking Horses, Section Commander, Troop Commander, Squadron Commander and Assistant Chief of the School. On promotion to Major General in 1900, Brusilov was added to the list of Household Troops (officers who might be retained on official business by the Tsar). During this time, Brusilov married (1884), and the union produced a son in 1887.

In 1902, as a Lieutenant General, he took command of the school, and under his leadership, the "Horse Academy" became an acknowledged centre of excellence in preparing staff officers for the cavalry. Brusilov published a number of papers on the use of cavalry, and visited France, Austria - Hungary and Germany to study riding tuition and stud management.

Brusilov was appointed to command the 2nd Guards Cavalry Division in 1906, but this was not a happy posting for him. The Revolution of 1905 had left St Petersburg in turmoil, and after his wife's death, he sought a posting away from the Guards and the capital.

In 1908, he was appointed to command the XIV Corps in the Warsaw Military District, where his tenure was notable for the improvements in combat training he implemented. He also remarried at this time, to Nadejda ("Hope") Jelihovski. Promoted to General of Cavalry in 1912, he became Deputy Commander - in - Chief of forces in the Warsaw Military District. The failures of the Russo - Japanese War had led to allegations that Generals from immigrant families, who made a significant fraction of the Russian Army's senior ranks, were less patriotic than those who traced their origins to within Russias borders, and Brusilov would come into conflict with the Governor - General in Warsaw, Georgi Skalon, and other "Russian - German" generals in that District. Brusilov was soon seeking another post.

In 1913, Brusilov was posted to command the XII Corps in the Kiev Military District, remarking on his departure, "I do not doubt, that my departure will produce a sensation in the troops of Warsaw region... Well! What’s done is done, and I am glad, that I have escaped cesspool of Skalon’s court atmosphere."

In July 1914, with the Russian army expanding on mobilization, Brusilov was promoted to command 8th Army, part of South - west Front, operating in Galicia. The 8th Army crushed the Austro - Hungarian forces before it, and rapidly advanced nearly 150 kilometers (94 miles). Reverses elsewhere along the Front, including the great defeat at Tannenberg, forced the 8th Army to retire in conformance with the general Russian withdrawal. For his victories, Brusilov was awarded the Order of Saint George 4th, and then 3rd Class. By a quirk of fate, several future White Army commanders held senior posts in 8th Army at this time — Brusilov's Quartermaster general was Anton Denikin, while Alexey Kaledin commanded the 12th Cavalry Division and Lavr Kornilov was in command of the 48th Infantry Division.

In the early part of 1915, Brusilov again advanced, penetrating the Carpathian passes and entering the Hungarian plain. At this time, Nikolai II visited the 8th Army and Brusilov was promoted to the rank of General - Adjutant (in the Imperial Russian Army this was a "four - star" General rank).

Once again, fortunes on other fronts would determine his actions and the Austrian - German breakthrough at Gorlice - Tarnów forced Brusilov to conform to the general retirement. By September, the 8th Army had withdrawn 180 kilometers (110 miles) to the Tarnopol region.

On 29 March 1916, Brusilov was given command of Southwest Front, and managed to secure a certain degree of freedom of action. Previous Russian offensives demonstrated a tendency to assault smaller and smaller sections of front with increasing density of artillery and manpower to achieve a breakthrough. The narrow frontage of these attacks made counterattacks straightforward for German forces, and this approach met with repeated failure for the Russians.

Brusilov decided to distribute his attack over the entirety of the Southwest Front. He hoped to disorganize the enemy over such a large area that some point would fatally give way. He decided not to waste resources by saturation bombardment of worthless areas, but to use interdiction fire against command posts, road networks, and other vital targets to degrade German command and control over the whole front. The noted German artillery commander, Georg Bruchmüller, having served opposite Brusilov's Front at this time, would learn from and adapt these tactics when planning the preparatory bombardment for Operation Michael on the Western Front in 1918. Brusilov was not even concerned with securing a great local advantage in manpower, permitting Divisions under his command to be transferred to other Fronts (so long as they attacked in support of his offensive).

Brusilov's new techniques were, by First World War standards, highly successful and over the next three months, the Southwest Front advanced an average of more than 30 kilometers along a front of more than 400 kilometres (250 miles), taking 400,000 Austro - Hungarian prisoners in the process. However, the planned supporting attack from the West Front (the Army group to Brusilov's north) was not delivered, and Germany was able to transfer 17 Divisions from France and Belgium to halt the Russian advance.

Brusilov would be awarded the Sword of Saint George with Diamonds for his greatest victory, one of only eight Russian commanders to receive this rare award during the First World War.

On 18 June 1916, an article "Hero of the Hour in Russia, Described Intimately by One Who Knows Him Well" by Brusilov's brother - in - law, Charles Johnson, appeareared in the New York Times.

• To increase the points of sally thereby preventing a concentration of the enemy's strategic reserve. The enemy is to be confused by several points of attack.
• To make the width of attack wide, greater than 30 kilometers.
• To limit the duration of bombardment, less than 5 hours.
• To advance artillery in secrecy and to cooperate with the infantry.
• To advance strategic reserve beforehand and to join with the storm troops after a breach of the enemy's front trench has been achieved. Not to avail cavalry.
• To get the trench lines as close as possible to the enemy's before the battle.

With the onset of revolution in Russia, Brusilov argued for the Tsar's abdication. When approached by Stavka for his opinion on the need for the abdication he replied, "... For the moment the only thing that matters is to stabilise our position to allow the continuation of the war with the external enemy... to abdicate in favour of Tsarevich Mikhail Alexandrovich and a council of regents... It is necessary to hurry, the faster to extinguish the flames [of revolution], otherwise we face innumerable catastrophic consequences."

In May 1917, Brusilov was appointed Commander in Chief of the Russian Army.

Throughout this period, Brusilov proved sympathetic to revolutionary aspirations, but his primary concern was that the war first needed to be won. In particular he asserted that until peace was achieved, the full authority of the central government must be respected, and that the army should maintain the full rigour of its disciplinary code. In a telegram to the Minister of War, Alexander Kerensky, he wrote, "... only the application of capital punishment will stop the decomposition of the army and will save freedom and our homeland".

This politically unpopular stand, together with the failure of the Kerensky Offensive in July 1917, led to Brusilov's replacement as Commander in Chief by his former deputy, Lavr Kornilov. Brusilov moved to Moscow and remained there at the disposal of the Provisional Government. When fighting broke out in Moscow following the October Revolution, Brusilov was severely wounded in the foot by a splinter of a shell that hit his bathroom.

Brusilov was torn by conflicting loyalties in the Revolution, and the Civil War that followed. His former soldiers were largely serving in the newly formed Red Army, and he concurred with the need for radical change, but as a conservative, patriot and monarchist his personal values were more in tune with those of the White faction.

Initially, Brusilov served on a special commission to determine the size and structure of the Red Army. Later, he led cavalry recruit training and became Inspector of Cavalry. He retired in 1924, but continued to carry out commissions for the Revolutionary Military Council.

Seventy when retired in 1924, he lived in his shared apartment with his sickly wife and another couple. He died in Moscow from congestive heart failure, and was given an honorable state funeral, buried at the Novodevichy Cemetery, by representatives from the 'new Russia' (the bolsheviks), and the 'old Russia' (the clergy, the middle and upper class).

According to the assessment of British Field Marshal Bernard Law Montgomery, Brusilov was one of the seven outstanding fighting commanders of World War I (the others being Falkenhayn, Ludendorff, Mustapha Kemal, Plumer, Monash and Allenby).