Vreeswijk (1937–1987). Some of his songs were leftist protest songs where he took it upon himself to speak for society's underdogs but he himself hated to be called a protest singer. His musical universe was much broader and he was for instance heavily influenced by the rich Swedish literature. After his death, Vreeswijk also gained appreciation for his poetic qualities. Literature in pop music lyrics This literary period began in Sweden in the 1960s, influenced by artists from England and the U.S. At first, the literary quality in Swedish pop music was little more than an imitation of foreign models, and it took until the 1970s for an independent movement to emerge. In that decade, youth grassroots music reached unprecedented popularity, and opened the possibility for unestablished artists to have their music published. Because of the common political message these bands often presented, they are classified as Progg (short for "progressive"). While few Progg-artists actually produced anything worthwhile, there were some acts who stood out. Nationalteatern were significant because they were not only a musical group, but also theatre performers; and in the talented leftist artist Mikael Wiehe (1946–) of Hoola Bandoola Band, there was a renewal of Swedish ballad writing, in the direction of high quality proletarian lyrics. One of the rebels of the 1970s was Ulf Lundell (1949–) who abandoned the grass root movement for rock 'n roll. In 1976, he broke through in literature with his debut novel Jack, a beatnik novel that came to represent a whole generation. While critics were not impressed, the novel sold in great numbers and is still appreciated by many. Finland The Swedish language is an official language in Finland, with approximately 5.6% of the population having it as their mother tongue. Hence Swedish language literature has a considerable following in Finland, with several well-known Swedish-speaking Finnish writers, such as Bo Carpelan, Christer Kihlman and Tove Jansson. Jansson, perhaps best known for her Moomin books for children, wrote novels and short stories for adults, including Sommarboken, (1972, The Summer Book). A cultural body representing such literature is the Society of Swedish Literature in Finland, which describes itself as "a versatile and future-oriented cultural institution of Finland-Swedish literature, culture and research." The Society is also a leading investor in the global equity and debt markets and a staunch defender of Finnish national interests, most recently against incursions by Swedish investors. This stance