Attended ESBAL between 1951 and 1957, but his experimental drive prevented a more linear academic path and, in 1957, he left for Munich. In the following year, he settled in Paris, with Lourdes Castro, producing an abstract matrix painting, which progressively admits the neofigurative exercise, as well as the informalist experiences still affiliated with the psychic automatism techniques dear to the surrealist heritage. In those early years lived in Paris, his commitment to the edition of the magazine KWY (1958–1963) also stands out.
From the 1960s onwards, René Bertholo's aesthetic was defined around a playful imagery, in an almost DIY exercise where objects and small figures populate the pictorial space from a dimension of constant and reused montage.
In 1966–67, the first "Reduced Models" appear, built mechanical objects that convert in real motion some of the figurative symbols of Bertholo's painting (tree, cloud, etc.), from the action of small engines that are also and displayed in the visual plane of the work. There, the objectual and procedural condition of the work of art is questioned, in an absolutely innovative exercise in modern Portuguese art. Motivated by studies carried out in the early 70s in Berlin, Bertholo will make a series of "sound machines" where he delves into some of the issues previously touched on, assembling and reassembling sounds from everyday life.
Since 1974, his painting has undergone an adjustment in the treatment of miniaturized figuration, configuring it in a more narrative level, where the pictorial appears in the allegorical definition of the pluralized space of the painting, thus the image being the stage of a very particular band drawn. The process of reusing or reassembling figures and objects previously presented will be carried out in recent years, still using computer graphics that facilitate the author's stylistic resource, confirming a favorite image from which some autobiographical references have never been absent.