Kalocsay has been described as the pillar of Esperanto poetry. In fact his influence pervades the entire literature and language theory of Esperanto. For more than a quarter of a century he inspired and guided the literary world of Esperanto through the revue Literatura Mondo (Literary World) and the publishing house of the same name. The Parnasa Gvidlibro (Guidebook to Parnassus), which he created in 1932 in collaboration with Gaston Waringhien, became the standard reference work for all aspiring poets and remains so today. His Streĉita Kordo (A Taut String) ranks among the two or three most outstanding collections of original poetry in the international language. His numerous translations are also considered to be the pinnacle of their art, his linguistic studies are still among the most widely consulted today, and his fostering of new talent opened doors for a score of contributors who might otherwise have remained in the shadows or abandoned the expression of their ideas in Esperanto.

Born in 1911, Kalocsay studied Medicine and went on to become chief surgeon at a leading Budapest Hospital. There is speculation that he learnt both Esperanto and Ido in adolescence but plumped for the former when he saw greater literary potential. In 1921, when his first original collection of poems was published - Mondo kaj Koro (A World and a Heart), readers and reviewers recognised that a powerful new voice was being heard for the first time in the original literature of the International Language. It was another 10 years before Streĉita Kordo appeared. This volume is an even more mature and polished showcase of his art and technical mastery. In seven cycles Kalocsay creates what is at times a very intimate poetry and at other times a poetry for all humanity, interpreting our longings with an epic scope . That same year Rimportretoj (Portraits in Rhyme) appeared - witty poems in rondello about several of the leading lights in the international language movement of that era.

In 1939 his next volume of poetry - Izolo (Isolation), was ready for publication, but couldn't be distributed because of the outbreak of war. A fresh edition eventually hit the market in the late seventies. In 1956, the year of the Hungarian uprising, Kalocsay recreated in verse, some of the better known of Aesop's fables, in Ezopa Saĝo (The Wisdom of Aesop). In 1971 La Kremo de Kalocsay (The Cream of Kalocsay) offered readers a selection of his earlier poems, then out of print.

Kalocsay's works on literary and linguistic theory include the monumental Plena Gramatiko de Esperanto (A Complete Grammar of Esperanto), written in collaboration with Gaston Waringhien, the style manual Lingvo Stilo Formo (Language Style Form), and a valuable poem on the art of poetry which appeared under the pseudonym C.E.R. Bumy in La Parnasa Gvidlibro.

From 1925 a bevy of outstanding translations appeared in the Esperanto community, in book form and in journals. Kalocsay was at the forefront, translating literary works from several languages. These include Petöfi's Johano la Brava (John the Brave) in 1923, Madach's La Tragedio de l'Homo (The Tragedy of Man) in 1924 (reiussued in 1965), Eterna Bukedo (Eternal Bouquet) - an anthology drawn from 22 languages in 1931, Goethe's Romaj Elegioj (Roman Elegies) in 1932, Hungara Antologio (Hungarian Anthology) in 1933; Dante's Infero in 1933, Baudelaire's La Floroj de l'Malbono (The Flowers of Evil) in 1957 , Shakespeare's Reĝo Lear in 1966, Heine's Kantoj kaj Romancoj (Songs and Romances) in 1969, and Petöfi's Libero kaj Amo (Freedom and Love) in 1970. The memorable partnership that Kalocsay had forged with Gaston Waringhien in producing La Parnasa Gvidlibro was revived to brilliant effect in the Heine and Baudelaire translations.

The group of writers which formed around the revue Literatura Mondo in the 1920s and 30s, came to be known as The Budapest School. Through the influence of their most eminent figure - Kalocsay, the writing of this group displayed a far superior technique and a more diverse range of themes than that of the bulk of their predecessors. Although romanticism was still the common motif, it was, in the words of William Auld, a "polished romanticism". Poetry in Esperanto lost its trait of dilettantism. The heights reached by Kalocsay and his colleagues spurred literary development, and for the first time, poetry in the international language could be compared favourably with that of the best national language poets. Undoubtedly, the advent of Kalocsay marked a watershed in the development of Esperanto culture. Kalman Kalocsay died in 1976, prompting a series of eulogies and retrospective articles in the Esperanto press, on a scale that hadn't been seen since Zamenhof's death.