An Esperantist (Esperanto: Esperantisto) is a person who speaks or uses Esperanto. Etymologically, an Esperantist is someone who hopes (from Esperanto esperanto "a hoping one", "someone who hopes", from esperi "to hope"). Although definitions of "Esperantist" vary, according to the Declaration of Boulogne ("Deklaracio pri la esenco de Esperantismo", declaration about the essence of esperantism), a document agreed at the first World Congress of Esperanto, an Esperantist is someone who speaks Esperanto and uses it for any purpose. An Esperantist is also a person who participates in Esperanto culture.
Lists of famous Esperantists
- Muztar Abbasi, Pakistani Scholar, Patron in chief of PakEsA, translated the Qur'an into Esperanto and many other works.
- William Auld, eminent Scottish Esperanto poet and nominee for the Nobel Prize for Literature
- Julio Baghy, poet, member of the Academy of Esperanto and "Dad" of the Esperanto movement.
- Henri Barbusse, French writer, honorary president of the first congress of the Sennacieca Asocio Tutmonda.
- Kazimierz Bein, "Kabe", prominent Esperanto activist and writer who suddenly left the Esperanto movement
- Émile Boirac, French writer and first president of the Esperanto language committee (later the Academy of Esperanto)
- Antoni Grabowski, the father of Esperanto poetry
- Boris Kolker, Esperantist scholar and key member of the Academy of Esperanto
- Georges Lagrange, French Esperantist writer
- John Edgar McFadyen
- Frederic Pujulà i Vallés, pioneer of Esperanto in Spain
- Sándor Szathmári, leading figure of Esperanto literature
- Ludwik Lejzer Zamenhof, Polish oculist and doctor, inventor of Esperanto.
- Kazimierz Badowski, founder of the Communist Party of Poland, promoted Esperanto as part of Trotskyist movement
- Richard Bartholdt, U.S. Representative from Missouri
- Robert Cecil, 1st Viscount Cecil of Chelwood, one of the architects of the League of Nations, awarded the Nobel Peace Prize
- Parley Parker Christensen, Utah and California politician
- Willem Drees, Dutch politician, Prime Minister of the Netherlands (1948–1958)
- Małgorzata Handzlik, member of the European Parliament
- Jean Jaurès, French politician. He proposed to the International Socialist Congress at Stuttgart in 1907 the use of Esperanto for the information diffused by the Brussels Office of the organization.
- Franz Jonas, President of the Republic of Austria, Secretary of the Austrian Laborist Esperantist League and founder of Internacio de Socialistaj Esperantistoj ("International of Socialist Esperantists")
- Heinz Fischer, President of the Republic of Austria
- Josip Broz Tito, head of state of Yugoslavia 
- Nadija Hordijenko Andrianova, Ukrainian writer and translator
- Ragnar Jaðimbalgsøn, Brazilian writer
- Ba Jin, prolific Chinese novelist and chairman of Chinese Writer Association
- Henri Barbusse, French writer, and honorary president of the first congress of the Sennacieca Asocio Tutmonda
- Louis de Beaufront, Esperantist writer
- Gerrit Berveling, Dutch Esperantist poet, translator and editor of the Esperanto literary review, Fonto
- Marjorie Boulton, British writer and poet in English and Esperanto; researcher and writer
- Jorge Camacho, Spanish Esperantist writer
- Vasili Eroshenko, Russian writer, Esperantist, linguist, and teacher
- Petr Ginz, native Esperanto speaking boy who wrote an Esperanto-Czech dictionary but later died in a concentration camp at age 16. His drawing of the Moon was carried aboard Space Shuttle Columbia. His diary appears in Czech, Spanish, Catalan and Esperanto, and was recently published in English.
- Don Harlow, Esperantist writer and webmaster of the United States
- Hector Hodler, Swiss journalist, translator, organizer, and philanthropist
- Hans Jakob, Swiss writer
- Kálmán Kalocsay, Hungarian surgeon, poet, translator, and editor
- Georges Lagrange, French Esperanto writer, member of Academy of Esperanto
- Nikolai Vladimirovich Nekrasov, Esperantist writer and translator of the Soviet Union
- Mauro Nervi, Italian poet in the Esperanto language
- Edmond Privat, Swiss author, journalist, university professor, and movement activist
- Cezaro Rossetti, Scottish Esperantist writer
- René de Saussure, Swiss writer and activist
- Teodoro Schwartz, Hungarian Jewish doctor, lawyer, author and editor
- William Thomas Stead, well-known philanthropist, journalist and pacifist who was aboard the RMS Titanic when it sank.
- Þórbergur Þórðarson (Thorbergur Thortharson), Icelandic writer and Esperantist
- J. R. R. Tolkien
- Leo Tolstoy, Russian writer and philosopher, who claimed he learned how to write Esperanto after two hours of study
- Vladimir Varankin, Russian writer
- Jules Verne, French author, incorporated Esperanto into his last unfinished work
- Daniel Bovet, Italian pharmacologist and winner of the 1957 Nobel Prize in Physiology or Medicine, learned Esperanto as a first language
- Sidney S. Culbert, American linguist and psychologist
- Bertalan Farkas, Hungarian cosmonaut
- Louis Lumière, French inventor of cinema,
said: "The use of Esperanto could have one of the happiest consequences in its effects on international relations and the establishment of peace."
- Wilhelm Ostwald, German Nobel laureate for his seminal work in chemical catalysis
- Claude Piron, Esperantist, psychologist, and linguist, translator for the United Nations
- Reinhard Selten, German economist and winner of the 1994 Nobel Memorial Prize in Economics because of his work on game theory. He has authored two books in Esperanto on that subject.
- Leonardo Torres y Quevedo, Spanish civil engineer and mathematician.
- Yrjö Väisälä, Finnish astronomer, discovered asteroids 1421 Esperanto and 1462 Zamenhof
- John C. Wells, British phonetician and Esperanto teacher
- Vladimir Köppen, Russian geographer of German descent
- Marcel Minnaert, Belgian astronomer who worked in Utrecht
- Bahá'í adherents, many of whom have been involved with Esperanto – see Bahá'í Faith and auxiliary language. Lidia Zamenhof was a Bahá'í, and several leading Baha'is have spoken Esperanto. Most notably the Son of Bahá'u'lláh, `Abdu'l-Bahá, learned Esperanto (see John Esslemont).
- Rudolf Carnap, German-born philosopher.
- Onisaburo Deguchi, one of the chief figures of the Oomoto religious movement in Japan and president of the Universala Homama Asocio ("Universal Human-love Association")
- Alfred Fried, recipient of a Nobel Peace Prize and author of a textbook on Esperanto
- Ebenezer Howard, known for his publication Garden Cities of To-morrow (1898), the description of a utopian city in which people live harmoniously together with nature
- Pope John Paul II, gave several speeches using Esperanto during his career
- Franko Luin, Swedish type designer of Slovene nationality
- John Eyton Bickersteth Mayor, English classical scholar, gave a historic speech against Esperanto reformists at the World Congress of Esperanto held at Cambridge
- Alexander Nedoshivin, tax specialist, one of the founders of the Esperanto Society at Kaunas, Lithuania
- Seok Joo-myung, Korean ecologist who studied and identified native butterflies of Korea
- William Main Page, Secretary of Edinburgh Esperanto Society, editor and author
- László Polgár, Hungarian chess teacher
- Susan Polgar, Hungarian-American chess grandmaster, taught Esperanto by her father László
- William Shatner, Canadian actor, recording artist, and author  [dubious ]
- George Soros, Hungarian-American billionaire and son of Esperantist parents ("Soros", a name selected by his father to avoid persecution, in Esperanto means "will soar")
- Daniel Tammet, British autistic savant, stated Esperanto as one of the ten languages he speaks
Information on William Thomas Stead from the Esperanto Vikipedio article.
- 100 eminentaj esperantistoj "100 eminent Esperantists" (eo)