Judoinfo.com, there is an article about Sarah Mayer, the first non Japanese woman black belt. An excerpt is below. The full article may be read here.
Sarah Mayer started Judo in London, England at the Budokwai, which
been founded by Gunji Koizumi on January 26, 1918. She visited Japan
1930's and studied at the Kodokan and later at the Kyoto Butokukai
been established in 1890 and was led by Kano's representatives). On
March 1, 1935 the Japanese Times bore the headline "Foreign Woman wins
Shodan at the Butokukai". Sarah Mayer was offered this rank on February
27, 1935 and was the first non-japanese
woman in the world to be awarded black belt rank in Kodokan Judo.
the same year to Britain, bringing Ichiro Hatta*
with her, and practiced at
the Budokwai for a while before setting up her own dojo in her home
Heath. Sarah was involved in the theatre and wrote a play "Hundreds
and Thousands" which played at the Garratt theatre in 1939. She went on
to write articles and
stories for the Evening Standard.
During Ms. Mayer's stay in Japan, which spanned about two years, she
letters to Gunji Koizumi. The following letters are reprinted courtesy
of Richard "Dicky" Bowen of the Budokwai and they reveal interesting
information about early