Kjartan Slettemark was a driving force on the Scandinavian art scene for less than half a century and a pioneer in both performance and art activism. With early actions like the occupation of Moderna Museet in Stockholm, his travels with a passport with a picture of a bearded Richard Nixon and his unexpected appearances of poodle costume, he soon became one of our most talked about artists.

Over time, he went from being an anti-authoritarian activist to creating works of a more introverted character. Instead of criticizing the system and power, his art took on a conciliatory stance. Kjartan Slettemark is perhaps best known for his collages, which are based on a photograph of the coffee-drinking American president Richard Nixon. S...