George Ivanovich Gurdjieff (Armenian: Գեորգի Իվանովիչ Գյուրջիև, Georgian: გიორგი გურჯიევი, Greek: Γεώργιος Γεωργιάδης, Russian: Гео́ргий Ива́нович Гюрджи́ев, January 14, 1866? – October 29, 1949) was considered a mystic and a spiritual teacher. He called his discipline "The Work" (connoting "work on oneself") according to Gurdjieff's principles and instructions, or (originally) the "Fourth Way". At one point he described his teaching as "esoteric Christianity".

At different times in his life, Gurdjieff formed and closed various schools around the world to teach the work. He claimed that the teachings he brought to the West from his own experiences and early travels expressed the truth found in ancient religions and wisdom teachings relating to self - awareness in people's daily lives and humanity's place in the universe. The title of his third series of writings, Life Is Real Only Then, When 'I Am', expresses the essence of his teachings. His complete series of books is entitled All and Everything.

Gurdjieff was born to a Greek father and Armenian mother in Alexandropol (now Gyumri, Armenia), then part of the Russian Empire. The Turks & Persians called Georgia 'Gurjistan', which may account for the root of the name "Gurdjieff". The exact date of his birth remains unknown (conjectures range from 1866 to 1877). Some authors (such as Moore) argue persuasively for 1866, others (like Patterson) for 1872; a passport gave a birth date of November 28, 1877, but he stated that he was born at the stroke of midnight at the beginning of New Year's Day (Julian calendar). Gurdjieff grew up in Kars and traveled to many parts of the world (such as Central Asia, Egypt and Rome) before returning to Russia for a few years in 1912. He later said: "Begin in Russia, end in Russia."

The only account of Gurdjieff's early life before he appeared in Moscow in 1912 appears in his book Meetings with Remarkable Men. This text, however, cannot be read as straightforward autobiography. In the pre 1912 period Gurdjieff went on his voyage outlined in Meetings with Remarkable Men where he comes upon a map of "pre-sand Egypt" which leads him to study with an esoteric group, the alleged Sarmoung Brotherhood.

From 1913 to 1949 the chronology appears to be based on material that can be confirmed by primary documents, independent witnesses, cross references, and reasonable inference. On New Year's Day in 1912, Gurdjieff arrived in Moscow and attracted his first students. In the same year he married the Polish Julia Ostrowska in St Petersburg. In 1914, Gurdjieff advertised his ballet, The Struggle of the Magicians, and supervised his pupils' writing of the sketch "Glimpses of Truth." In 1915, Gurdjieff accepted P. D. Ouspensky as a pupil, while in 1916 he accepted the composer Thomas de Hartmann and his wife Olga as students. At this time he had about thirty pupils.

In the midst of revolutionary upheaval in Russia, he left Petrograd in 1917 to return to his family home in Alexandropol. During the Bolshevik Revolution, Gurdjieff set up temporary study communities in Essentuki in the Caucasus, then in Tuapse, Maikop, Sochi and Poti, all on the Black Sea coast of southern Russia, where he worked intensively with many of his Russian pupils.

In March 1918, Ouspensky separated from Gurdjieff. Four months later, Gurdjieff's eldest sister and her family reached him in Essentuki as refugees, informing him that Turks had shot his father in Alexandropol on 15 May during the Armenian Genocide (1915 – 1923). As Essentuki became more and more threatened by civil war, Gurdjieff put out a fabricated newspaper story announcing his forthcoming "scientific expedition" to Mount Induc. Posing as a scientist, Gurdjieff left Essentuki with fourteen companions (excluding Gurdjieff's family and Ouspensky). They traveled by train to Maikop, where hostilities delayed them for three weeks. In spring 1919, Gurdjieff met the artist Alexandre Salzmann and his wife Jeanne and accepted them as pupils. Assisted by Jeanne Salzmann, Gurdjieff gave the first public demonstration of his Sacred Dances (Movements at the Tbilisi Opera House, 22 June).

In the autumn of 1919, Gurdjieff and his closest pupils moved to Tbilisi, formerly known as Tiflis. There Gurdjieff's wife, Julia Ostrowska, Mr and Mrs Stjoernval, Mr and Mrs de Hartmann and Mr and Mrs de Salzmann gathered a lot of the fundamentals of his teaching. Gurdjieff concentrated on his still unstaged ballet, The Struggle of the Magicians; Thomas de Hartmann (who had made his debut years before as the Czar of All Russia) worked on the music for the ballet; and Olga Iovonovna Lazovich Milanoff Hinzenberg (who years later wed the American architect Frank Lloyd Wright) practiced the ballet dances. In 1919, Gurdjieff established his first Institute for the Harmonious Development of Man. He was thought to be greatly influenced by Nikolai Marr, a Georgian archaeologist and historian.

In late May 1920, when political conditions in Georgia changed and the old order was crumbling, his party traveled by foot to Batumi on the Black Sea coast and then to Istanbul. Gurdjieff rented an apartment on Koumbaradji Street in Péra, and later at 13 Abdullatif Yemeneci Sokak near the Galata Tower. The apartment is near the kha’neqa’h (monastery) of the Molavieh Order of Sufis (founded by Jalal al-Din Muhammad Rumi), where Gurdjieff, Ouspensky and Thomas de Hartmann experienced the sema ceremony of The Whirling Dervishes. In Istanbul, Gurdjieff also met Captain John G. Bennett, then head of British Military Intelligence in Constantinople. Later, Bennett would become a follower of Gurdjieff and of Ouspensky.

In August 1921 and 1922, Gurdjieff traveled around western Europe, lecturing and giving demonstrations of his work in various cities, such as Berlin and London. He attracted the allegiance of Ouspensky's many prominent pupils (notably the editor A.R. Orage). After he lost a civil action to acquire Hellerau possession in Britain, Gurdjieff established the Institute for the Harmonious Development of Man south of Paris at the Prieuré des Basses Loges in Fontainebleau - Avon near the famous Château de Fontainebleau. Gurdjieff acquired notoriety as "the man who killed Katherine Mansfield" after Katherine Mansfield died there of tuberculosis under his care on 9 January 1923. However, James Moore and Ouspensky convincingly show that Katherine Mansfield knew she would soon die, and that Gurdjieff made her last days happy and fulfilling.

Starting in 1924 Gurdjieff made visits to North America, where he eventually received the pupils taught previously by A.R. Orage. In 1924, while driving alone from Paris to Fontainebleau, Gurdjieff had a near fatal car accident. Nursed by his wife and mother, he made a slow and painful recovery — against medical expectation. Still convalescent, he formally "disbanded" his Institute on 26 August (in fact he dispersed only his less dedicated pupils), and began writing All and Everything.

In 1925 Gurdjieff's wife contracted cancer; she died in June 1926 in spite of radiotherapy and Gurdjieff's magnetic treatments. Ouspensky attended her funeral. According to Fritz Peters, Gurdjieff was in New York from November 1925 to the spring of 1926, when he succeeded in raising over $1,000,000.

In 1935 Gurdjieff stopped writing All and Everything. He had completed the first two parts of the trilogy but only started on the Third Series. (It was later published under the title Life Is Real Only Then, When 'I Am'). In Paris, Gurdjieff lived at 6 Rue des Colonels - Rénard, where he continued to teach throughout World War II.

Gurdjieff died on October 29, 1949 at the American Hospital in Neuilly - sur - Seine, France. His funeral took place at the St. Alexandre Nevsky Russian Orthodox Cathedral at 12 Rue Daru, Paris. He is buried in the cemetery at Fontainebleau - Avon.