Leif Erikson Day
America Not Discovered by Columbus by Rasmus B. Anderson was published in 1874. This book helped make popular the idea that Vikings were the first Europeans in the New World. In 1925, American President Calvin Coolidge recognised Leif Erikson as the Discoverer of America. This was due to research by Norwegian-American scholars such as Knut Gjerset and Ludvig Hektoen.