Paul Detlefsen, (3 October, 1899 - 1 August, 1986), was an artist whose greatest works were produced from around the mid to late 20th century. He was born in Denmark, in the country's capital of Copenhagen. He later moved to the US where, at a later age, studied arts at the School of the Art Institute of Chicago. After completing his studies at the school, he moved to Hollywood with the desire to establish himself as a cartoonist. That never worked for him, forcing him to switch to developing film backdrops for different productions. He worked with Warner Brothers Studios where he developed several backdrops for different films. While at Warner, Detlefsen rose to become the head the studio's art department. He has been credited for several works, including The Horn Blows At Mid Night, and Shadow of a Woman. His work for The Adventures of Mark Twain film earned him a nomination at the 1944 17th Academy Awards. He also worked for companies such as Cecil B. DeMille and Walt Disney.
At the age of 50 Detlefsen he decided to focus on calendar art. He created so many pieces, most of which were reproduced by reputable companies such as Brown and Bigelow Company and Vernon Company. Some of his artworks including oil paintings were later lithographed to produce calendars, table mats, puzzles, wall murals, and more. Detlefsen's first calendar, which was based on landscape art and named "The Good Old Days," was published in 1951. The calendar became an immediate success, passing as the second most popular calendar in its year of publication. Detlefsen is one of the few artists who chose to use their family members as models for their artworks. His paintings thus featured beautiful rural landscapes with his children, grandchildren, family members and friends acting as his models.