The term was popularised by the linguistic and cultural Scandinavist movement, which asserted the common heritage and cultural unity of the Scandinavian countries and rose to prominence in the 1830s. The popular usage of the term in Sweden, Denmark and Norway as a unifying concept became established in the nineteenth century through poems such as Hans Christian Andersen's "I am a Scandinavian" of 1839. After a visit to Sweden, Andersen became a supporter of early political Scandinavism. In a letter describing the poem to a friend, he wrote: "All at once I understood how related the Swedes, the Danes and the Norwegians are, and with this feeling I wrote the poem immediately after my return: 'We are one people, we are called Scandinavians!'".