After World War II, as the Kato family bonsai nursery struggled to survive, the American occupational forces requested bonsai classes. The Americans also purchased New Year plants of "Sho-Chiku-Bai" (Pine-Bamboo-Flowering Apricot representing the "Three Friends of Winter") when most Japanese could not purchase such luxuries. Saburo Kato has generously credited the interest, encouragement and assistance of the Americans in rebuilding bonsai as a beloved part of Japanese life.
At the Expo '70 Osaka World Fair, the Nippon Bonsai Association hosted an outstanding bonsai exhibit that introduced the world to the beauty of bonsai.
Bonsai was only a small part of the world fair but because the exhibition was open for many months, more international visitors were exposed to bonsai than ever before.
International interest in bonsai surged! Many new bonsai lovers enthusiastically pursued the study of bonsai and its related art forms. Those already training bonsai in relative isolation became catalysts to form clubs. Expo '70 brought Saburo Kato and the Japanese bonsai community together with Hawaii's Haruo "Papa" Kaneshiro, California's John Naka, Germany's Paul Lesniewicz, India's Nikunj Parekh, and many others who became a unique generation of international bonsai leaders.
Saburo Kato and the Japanese bonsai community were impressed with the universal interest and appreciation for the beauty of bonsai. Even those who had known Japan as an enemy during World War II found equanimity after viewing and learning of bonsai. As Japan became a nation dedicated to world peace, it became apparent that bonsai could be a bridge to international friendships and peace. The world fair had been a significant financial success, and the Expo '70 Osaka Commemorative Association very generously supported the efforts of the Nippon Bonsai Association.
In the spring of 1980, the Nippon Bonsai Association organized the International Bonsai & Suiseki Exhibition at the Expo '70 Osaka
The World Bonsai Conference in Osaka, Japan 1980
Memorial Park with the cooperation and participation of bonsai organizations throughout the world.
These exhibitions were held annually thereafter through 1989. Bonsai tour groups and individuals who visited these exhibitions became a part of the international bonsai movement. With the help of Expo '70 funds, bonsai leaders representing 11 countries participated in a World Bonsai Conference in 1980, and they resolved to establish a world bonsai organization "to unite the people of the world in a spirit of peace."
At the 1980 International Bonsai Congress in Hawaii (IBC '80 Hawaii), co-sponsored by Bonsai Clubs International and the Hawaii Bonsai Association, the Nippon Bonsai Association participated internationally outside of Japan for the first time. Saburo Kato created his beautiful "Peace Forest" and gave his now famous "Bonsai No Kokoro (The Spirit and Philosophy of Bonsai)" address. In the following years, the Nippon Bonsai Association provided lecturer-demonstrators who taught bonsai throughout the world.
In 1989, a World Bonsai Convention was held in Japan for first time. Many large scale bonsai events had been held in the western world but it was truly the first major international bonsai event which was held in the Orient. The theme for the convention was "World Peace through Bonsai"