He is considered a literary iconoclast and, alongside William S. Burroughs and Allen Ginsberg, a pioneer of the Beat Generation. Kerouac is recognized for his method of spontaneous prose. Thematically, his work covers topics such as Catholic spirituality, jazz, promiscuity, Buddhism, drugs, poverty, and travel. He became an underground celebrity and, with other beats, a progenitor of the hippie movement, although he remained antagonistic toward some of its politically radical elements. In 1969, aged 47, Kerouac died from internal bleeding due to long-term alcohol abuse. Since his death, Kerouac’s literary prestige has grown, and several previously unseen works have been published.