Theodore Philip Stephanides (Greek: Θεόδωρος Φίλιππος Στεφανίδης; 21 January 1896 – 13 April 1983) was a Greek-British doctor and polymath, best remembered as the friend and mentor of Gerald Durrell. He was also known as a naturalist, biologist, astronomer, poet, writer and translator.

Stephanides' autobiographical account of the Battle of Crete, Climax in Crete (1946), is still cited by military historians and his 1948 A Survey of the Freshwater Biology of Corfu and of Certain Other Regions of Greece is a definitive biological treatise on the freshwater life in Corfu.

He was portrayed in a number of books, including My Family and Other Animals by Gerald Durrell, Prospero's Cell by Lawrence Durrell, The Colossus of Maroussi by Henry Miller as well as in several movies and TV productions, and has four biological species named after him.

Childhood in Bombay and Corfu Theodore Philip Stephanides was born on 21 January 1896 in Bombay, British India (present-day India), to Philip (Philippos) Stephanides, a native of Thessaly, Ottoman Empire, and Caterina Ralli, of Greek descent, born and educated in London."Theodore Stephanides: A Brief Biography" (author not mentioned; it could be Richard Pine or Anthony Hirst), in Theodore Stephanides, Autumn Gleanings: Corfu Memoirs and Poems, Durrell School of Corfu & International Lawrence Durrell Society, 2011, pp. 12–18. Stephanides' father worked for a company that belonged to Ralli Brothers, a British family of Greek origin, while Stephanides' mother was part of that family. Stephanides spent his early years in Bombay, and since his family only spoke English at home, it was his first language.Vera Konidari, "Theodore Stephanides, Man of Letters", in Paschalis Nikolaou (ed.), Encounters in Greek and Irish Literature: Creativity, Translations and Critical Perspectives, Cambridge Scholars Publishing, 2020, pp. 192–198, .

In 1907, as Stephanides' father retired, the family moved first to Marseilles, France, and shortly afterwards to Rallis' estate in Corfu.Vera Konidari, "Theodore Stephanides: Trailing the Islands of His Mind", in Richard Pine, Vera Konidari (eds.), Islands of the Mind: Psychology, Literature and Biodiversity, Cambridge Scholars Publishing, 2020, pp. 140–155, . It was only then that Stephanides began to learn Greek, at the age of 11. He would speak Greek with a strong British accent.Lawrence Durrell, Prospero's Cell, London: Faber and Faber, 2000, p. 6.

World War I and the Greco-Turkish War (1919–1922) Stephanides served as a gunner in the Greek army on the Macedonian front in 1917–1918.Anthony Hirst, "Theodore Stephanides at the Macedonian Front, 1917–1918", presentation (Saturday 12 May 2018) at the Conference "The Macedonian Front 1915–1918: Politics, Society & Culture in Time of War", Thessaloniki, May 10–13, 2018. Following that, he participated in the Greco-Turkish War of 1919–1922. Subsequently, he would write Macedonian Medley; 1917–1918, an account of his participation in the Macedonian campaign, based on a diary he kept during that time. For 18 months, he served in a relatively calm and stable area, south of Ghevgheli and near the towns of Kilkis and Isvor. He often acted as a liaison with British and French units, owing to his knowledge of English and French.

In 1921–1922, Stephanides was detained and court-martialed for "insulting" King Constantine I of Greece, after he refused to take part in a December 1921 service which celebrated the king's return to Greece. The incident was caused by Stephanides' resentment with the Greek military authorities and his political views: he was a strong supporter of Eleftherios Venizelos,Lawrence Durrell, Prospero's Cell (2000), p. 5. the prime-minister of Greece in 1910–1920, who was in conflict with Constantine I.Richard Clogg, A Concise History of Greece, London: Cambridge University Press, 2002, p. 95, .

1920s: study of medicine in Paris, translation of poetry After his demobilization, Stephanides moved to France, where he studied medicine at the University of Paris (specialization of radiology) between 1922 and 1928, one of his professors being Marie Curie.Marios-Byron Raizis, "Lawrence Durrell and the Greek Poets: A Contribution to Cultural History", in Anna Lillios (Ed.), Lawrence Durrell and the Greek World (Susquehanna University Press, 2004), pp. 250–252. In 1929, he defended his Ph.D. thesis on microscopy techniques, at the same university.

While in Paris, Stephanides also practiced astronomy and was highly regarded by Camille Flammarion, a French astronomer. Stephanides' professional interest in astronomy dates back to as early as the summer of 1914, when he observed the Sun for two months and made 24 drawings of various groups of sunspots."Société Astronomique de France. Séance du Dimanche 7 Février 1915", in L'Astronomie, 1915, vol. 29, pp. 83–94. For this research, he was made member of the French Astronomical Society in February 1915. Stephanides would continue making astronomical observations until the end of his life.

In the 1920s, Stephanides began his work as a translator of Greek poetry into English. In 1925 and 1926, he published two volumes of Greek poems belonging to Kostis Palamas"Editor's Introduction" (by Richard Pine), in Autumn Gleanings: Corfu Memoirs and Poems (2011), pp. 9–11. and other modern Greek poets. These translations were coauthored with George Katsimbalis, the man portrayed in Henry Miller's novel The Colossus of Maroussi along with Stephanides himself and Lawrence Durrell.Henry Miller, The Colossus of Maroussi, London: Seeker and Warburg, 1942. They met during World War I and would become lifelong friends and collaborators.

1930s: radiology practice in Corfu, meeting the Durrell family Stephanides returned to Corfu in 1928. The same year, along with his friend Philoctetes Paramythiotis (1893–1996), Stephanides founded the first radiological laboratory of the Ionian Islands. They co-directed the X-ray unit until 1938, when Stephanides moved to Thessaloniki. A somewhat fictionalized account of Stephanides' work at the radiological laboratory appears in The Durrells series (season 3), with young Margo Durrell acting as his assistant.

In 1930, Stephanides married Mary Alexander, the granddaughter of a former British consul in Corfu. The couple had one child, Alexia Stephanides-Mercouri (1931–2018). Alexia was a close friend of Gerald Durrell in Corfu, and Stephanides hoped that the two would marry one day, but the outbreak of World War II ruined these plans. Alexia went on to marry Spyros Mercouris (1926–2018), the brother of Greek actress Melina Mercouri. They had two children, Pyrrhus and Alexander Mercouris.

Stephanides grew interested in freshwater biology in the 1930s. In 1936, following instructions from the Greek government, he started to work on his scientific magnum opus, a treatise on the freshwater biology of Corfu, which would be published in 1948. During his research, Stephanides discovered three microscopic water organisms, Cytherois stephanidesi, Thermocyclops stephanidesi and Schizopera stephanidesi.

In the summer of 1935, Stephanides made the acquaintance of the Durrell family, who had recently moved to Corfu.Joanna Hodgkin, Amateurs in Eden, Virago Press, 2012, pp. 164–165. He quickly developed a close friendship with two of the Durrell brothers, Lawrence and Gerald, who would remain his lifelong friends. As Gerald Durrell would later recall, Stephanides produced an enormous effect upon him, "a budding naturalist of ten" at that time, helping him develop his exploration skills. "Not many young naturalists have the privilege of having their footsteps guided by a sort of omnipotent, benign and humorous Greek god," wrote Durrell.Theodore Stephanides, Island Trails, Introduction by Gerald Durrell, pp. ix–xi.

The two Durrell brothers would feature Stephanides in their memoirs of the time they spent in Corfu: Gerald in his Corfu trilogy (which includes the bestseller My Family and Other Animals, first published in 1956),Gerald Durrell, The Corfu Trilogy, London: Penguin Books, 2006. and Lawrence in Prospero's Cell (first edition: 1945).Lawrence Durrell, Prospero's Cell, London: Faber and Faber, 2000. Stephanides, too, would write memoirs on that period, which consist mostly of reminiscences about Lawrence Durrell and his then-wife, Nancy. Fragments from them were published by the Deus Loci journal in the 1970s and 1980s, while the full version appeared in 2011 under the title Corfu Memoirs in the collection of Stephanides' works Autumn Gleanings.

During 1938 and 1939, Stephanides participated in the anti-malaria campaign in Salonica and Cyprus, organized by the Rockefeller Foundation. Earlier, in 1933, Stephanides drew up a report on anti-malaria measures to be performed in Corfu, based on directives from the Corfiot health authorities.

As Stephanides came back to Corfu in 1939, for a brief period, he made an acquaintance with Henry Miller, who later remembered: "Theodore is the most learned man I have ever met, and a saint to boot."Henry Miller, The Colossus of Maroussi (1942), p. 15.

At the outbreak of World War II, Stephanides had to leave Corfu again and would only return there on rare occasions. Nevertheless, he would keep fond memories of the island and the influence it produced on him.

World War II, memoir Climax in Crete During World War II, being a British citizen, Stephanides served as a medical officer (lieutenant, and later major) in the Royal Army Medical Corps of the British Army in continental Greece, Crete, the Sahara and Sicily.Michael Haag, The Durrells of Corfu, Profile Books, 2017, p. 171, . In May 1941, Stephanides was in Crete with the Allied forces during the German invasion. As the Allies were retreating across the island to be evacuated by sea, Stephanides walked in boots several sizes too large, which made him limp for some time after that.Ian MacNiven, Lawrence Durrell: A Biography, Faber & Faber, 1998, pp. 234–235. During the last stage of their long and exhausting march, he and another medical officer took charge of a group of about one hundred walking wounded, and they had to walk in open under the protection of the Red Cross flag, without any weapons or even steel helmets.The Campaign in Greece and Crete, War Office, 1942, p. 63. Eventually, they succeeded in reaching the embarkation beach and were evacuated by H.M.A.S. Perth to Alexandria.Antony Beevor, Crete: The Battle and the Resistance, Penguin Books, 2014, pp. 216, 231, .

In 1946, Stephanides published Climax in Crete, an eyewitness account of the Battle of Crete. Lawrence Durrell wrote a foreword to it, where he remarked: "For clearness, accuracy, and unselfconsciousness [this account] is quite fit to rank beside the compilations of any modern Purchas... It evokes the atmosphere of Greece and Crete during the German attack with a fidelity I have not seen elsewhere equalled; and to those who were there it will no doubt come as a refreshment after the scrappy sensational prose works of the professional journalists."Theodore Stephanides, Climax in Crete, Foreword by Lawrence Durrell, pp. 5–6. Lawrence's brother, Gerald Durrell, mentioned that Climax in Crete was "one of the best war books written". Alan G. Thomas also praised it, saying that it was "one of the best individual accounts of a campaign written from the human point of view".Lawrence Durrell, Spirit of Place: Essays and Letters on Travel, edited by Alan G. Thomas, New York: E.P. Dutton and Co., 1969, p. 57. Climax in Crete is quoted extensively by English military historian Antony Beevor in his book Crete: The Battle and the Resistance.Antony Beevor, Crete: The Battle and the Resistance, Penguin Books, 2014.

Stephanides' parents were killed in Corfu during the 1943 German bombing of the island, while his wife Mary and daughter Alexia had moved to England in 1939 and stayed safe until the end of the war, living with the Durrells in Bournemouth for some time.