Karl Maier (1901 – 25 July 2000) was a German Esperantist and member of the Universala Esperanto Asocio, for more than 50 years.
After emigration from Germany in 1930, he was living with Esperanto enthusiasts among United States, Mexico and Japan.
After his return to Germany, he managed to unite several esperantists, reaching over 300 subscribers for the Chinese magazine El Popola Ĉinio (The Chinese People); promoted the regular Esperanto conventions in East Berlin (beginning in 1960) and fought for the legalization of the Esperanto language in the GDR.
Maier’s testament established that his fortune should be donated to the Esperanto-Ligo Berlin and the Esperanto Movement in China.
The Berlin part of the inheritance was invested to build the Germana Esperanta Kultura Centro, new home of the Berlin Esperanto Movement.