Leon Isserlis (1881–1966) was a Russian-born British statistician known for his work on the exact distribution of sample moments, including Isserlis’ theorem. He also brought to the attention of British statisticians the work of Russian mathematicians and statisticians, including Chebyshev and Chuprov. In 1926 he wrote a review for the Journal of the Royal Statistical Society of R. A. Fisher's seminal book Statistical Methods for Research Workers. The review was rather critical, particularly of Fisher's lack of references to earlier work by others such as Chebyshev.