Born in Osaka, Japan.
Became interested in art and attended the studio of Jiro Yoshihara, where he produced his first works, Ana (Holes).
Together with other young artists close to master Yoshihara he took part in an exhibition called "Seven Avant-garde Artists" held at the Kintetsu department store in Osaka.
Graduates from the Kansai Gakuin University.
Won the Asahi Award at the Kansai art exhibition and the Association Award at the Association of Modern Art Exhibition.
Takes part in the "First Exhibition of the Genbi Group", the movement founded by Muramatsu Hiroshi but of which Yoshihara is the true driving force.
The event, held at the Asahi Biru Gallery in Kobe brought together the group of young artists who were soon to found the Gutai Group.
Under Yoshihara's guidance, Shimamoto and the master’s other students found the Gutai Movement of Concrete Art. The name was Shimamoto's suggestion. He put his house at their disposal, and it became the official headquarters of the group. The "Gutai" bulletin, the official Association review was printed here.
The first "Gutai" bulletin is printed: it contains some illustrations of works by the artists of the group, including one by Shimamoto. The members of Gutai, after joining forces with the members of the Zero Group (Tanaka, Shiraga, Murakami, Kanayama), take part in the "Seventh Exhibition of the Independent Yomiuri", an event that the Tokyo Metropolitan Museum held each year to give young artists an audience. On this occasion their works are signed Gutai.
During the “First Open Air Exhibition of Modern Art: to challenge the mid-summer sun”, the first independent meeting of the Gutai Group held in the Ashiya pine wood, Shimamoto exhibits a metal sheet with small perforations, painted white on one side and blue on the other. In the evening a lamp illuminated the sheet from behind creating an effect similar to that of a starry sky.
In the same year, Shimamoto takes part in the “First Gutai Exhibition” held indoors, at Ohara Kaikan in Tokyo: for the occasion he presents the work Please, walk on this made up of a series of wooden boards on a system of springs that make it difficult to walk on. The artist will go on to produce various reconstructions of this work in the nineties.
On the occasion of the "Second Open Air Exhibition of Modern Art", Shimamoto puts on Performance of Destruction where he experiments with a new technique: shooting little bags full of paint from a cannon to a musical background.
In October 1956, the Gutai Group holds a second exhibition at Ohara Kaikan in Tokyo: Shimamoto places a huge canvas on the floor. In the centre he places a rock, against which he throws bottles with different coloured pigment inside. This is the first bottle crash experiment using a technique which will significantly affect his future work.
“Life” magazine does a cover story on Shimamoto.
Takes part in the first “Gutai Art on the Stage" exhibition at the Sankei Center in Osaka: here he presents his pioneering video and sound works. Involved in the “First exhibition of young Asahi talent” at the Takashimaya department store in Osaka.
At the second “Gutai Art on the Stage” exhibition at the Asahi Kaikan, he projects two different films made by himself on the same screen.
This is what he said about it: “For this event I decided to do something called ‘the movie never seen all over the world”. He drew points and lines on a used 35 mm film given to him by a former pupil of his, washed in vinegar by Shimamoto himself.
The second evening of "Gutai Art on the Stage" was part of the International Festival of Osaka, an event which included the “International Art in a New Era. Informal and Gutai” exhibition at the Takashimaya department store. Here the Gutai Group strengthened its links with the French critic Michel Tapié, whom they had met the previous year when he visited Japan accompanied by the artist Georges Mathieu.
The BBC film him at Toyosaki School as he works on an action painting consisting in throwing glass bottles filled with paint.
An event called “Arte Nuova” is held in Palazzo Granieri at the Turin International Festival. Around a hundred works by European, American and Japanese artists (Gutai and Informal) are displayed.