Leach was born in Hong Kong, but spent his first years in Japan, until his father moved back to Hong Kong in 1890. Later, he attended Slade School of Fine Art, where he studied etching. Reading books of Lafcadio Hearn he became interested in Japan.
1909 he arrived in Japan for a second time. At Tokyo he taught etching, also talks about etching, also about the ideas of William Morris. The meetings were attended by Mushanokōji Saeatsu, Shiga Naoya, Yanagi Sōetsu and others from the "Shirakaba-Group", who were trying to introduce western art to Japan after 250 years of seclusion. In etching, Satomi Ton, Kojima Kikuo, and later Ryūsei Kishida, became pupils of Leach.
About 1911 he became fascinated by pottery of Raku-yaki-style, and through introduction by Ishii Hakuti he began to study under Urano Shigekichi 浦野繁吉, 1851-1923), who stood as Kenzan 6th in the tradition of potter Ogata Kenzan (1663 -1743). Helping as interpreter for technical terms was the potter Tomimoto Kenkichi, whom he had met already earlier. From this time Leach wrote articles for the Shirakaba.
1913 he also drafted covers for Shirakaba and "Fyūzan" Attracted by the in Peking living Prussian philosopher and art scholar Dr. Alfred Westharp he moved 1915 to Peking and took there the Name 李奇聞 (for "Leach"), but returned the following year to Japan. - It was the year 1919, when young Hamada Shōji visited Leach for the first time. Leach received a kiln from Kenzan and built it up in Yanai’s garden and called it Tōmon-gama. Now established as a potter, he decided to move to England.
In 1920, before leaving, he had an exhibition in Osaka, where he met the great potter Kawai Kanjirō. In Tokyo, a farewell exhibition was organized. Back in England
Leach had the ambition of establishing a kiln in England, but he had little experience in this aspect of ceramic produ.landscape in search of a suitable site, the two established the Leach Pottery at St. Ives, Cornwall in 1920. They chose to build a traditional Japanese wood burning kiln, the first built in the West,The two of them promoted pottery as a combination of Western and Eastern arts and philosophies. In their work they focused on traditional Korean, Japanese and Chinese pottery, in combination with traditional techniques from England and Germany, such as slipware and salt glaze ware. They saw pottery as a combination of art, philosophy, design and craft – even as a greater lifestyle. However, many in the West considered their pottery crude by the refined standards of the day. Publishing A Potter's Book in 1940 defined Leach's craft philosophy and techniques, and became his breakthrough to recognition.
In the 1930s Leach met Mark Tobey, a fellow artist and teacher at Faith. In 1934, Tobey and Leach traveled together through France and Italy, then sailed from Naples to Hong Kong and Shanghai, where they parted company, Leach heading on to Japan. Leach formally joined the Bahá'í Faith in 1940. A pilgrimage to the Bahá'í shrines in Haifa, Israel, during 1954 intensified his feeling that he should do more to unite the East and West by returning to the Orient "to try more honestly to do my work there as a Bahá'í and as an artist..." Midlife
Leach advocated simple and utilitarian forms. His ethical pots stand in opposition to what he called fine art pots, which promoted aesthetic concerns rather than function. Popularized in the 1940s after the publication of A Potter's Book, his style had lasting influence on counter-culture and modern design in North America during the 1950s and 1960s. Leach's pottery produced a range of "standard ware" handmade pottery for the general public. He continued to produce pots which were exhibited as works of art.
Many potters from all over the world were apprenticed at the Leach Pottery, and spread Leach's style and beliefs. His British associates and trainees include Michael Cardew, Katherine Pleydell-Bouverie, Nora Braden, David Leach and Michael Leach (his sons), Janet Darnell (whom Leach married, 1956), William Marshall, Sylvia Hardaker, Kenneth Quick and Richard Batterham. His American apprentices include Warren MacKenzie (who likewise influenced many potters through his teaching at the University of Minnesota), Byron Temple, Clary Illian and Jeff Oestrich. He was a major influence on the leading New Zealand potter Len Castle who travelled to London to spend time working with him in the mid-1950s. Many of his Canadian apprentices made up the pottery scene of the Canadian west coast during the 1970s in Vancouver.
Leach was instrumental in organizing the only International Conference of Potters and Weavers in July 1952 at Dartington Hall, where he had been working and teaching. It included exhibitions of British pottery and textiles since 1920, Mexican folk art, and works by conference participants, among them Shoji Hamada and US-based Bauhaus potter Marguerite Wildenhain. Another important contributor was Japanese aesthetician Soetsu Yanagi, author of The Unknown Craftsman. According to Brent Johnson, "The most important outcome of the conference was that it helped organize the modern studio pottery movement by giving a voice to the people who became its leaders…it gave them [Leach, Hamada and Yanagi] celebrity status…[while] Marguerite Wildenhain emerged from Dartinghall Hall as the most important craft potter in America." Later years
He continued to produce work until 1972 and never ended his passion for travelling, which made him a precursor of today's artistic globalism. He continued to write about ceramics even after losing his eyesight. The Victoria and Albert Museum in London held a major exhibition of his art in 1977. The Leach Pottery still remains open today, accompanied by a museum displaying many pieces by Leach and his students.