Ludwig Bemelmans (April 27, 1898 – October 1, 1962) was an Austrian and American writer and illustrator of children's books and adult novels. He is known best for the Madeline picture books. Six were published, the first in 1939.

Bemelmans was born on April 27, 1898, to Belgian painter and hotel owner Lambert Bemelmans and the German Frances Fischer in Meran, Austria-Hungary (now Italy). He grew up in Gmunden on the Traunsee in Upper Austria. Bemelmans' first language was French and his second German.

In 1904, Lambert left his wife and Ludwig's governess, both of whom were pregnant with his children, for another woman, after which Frances took Ludwig and his brother to her native city of Regensburg, Germany. Bemelmans had difficulty in school, as he hated the German style of discipline. Bemelmans was apprenticed to his uncle Hans Bemelmans at a hotel in Austria. In a 1941 New York Times interview with Robert van Gelder, Bemelmans related that while an apprentice, he was regularly beaten and whipped by the headwaiter. According to Bemelmans, he finally warned the headwaiter that if he was whipped again, Bemelmans would retaliate with a gun. The headwaiter ignored his warning, whipped him, and Bemelmans reportedly shot and seriously wounded him in retaliation. Given the choice between reform school and emigration to the United States, Bemelmans chose the latter. It is likely that this was one of Bemelmans' famous yarns, because in John Bemelmans Marciano's biography of his grandfather, Bemelmans relates a simpler story: recognizing that Ludwig was an incorrigible boy, his uncle offered him the choice of going to America (where his father now lived), or going to reform school.

Bemelmans spent the next several years working at hotels and restaurants in the United States. In 1917, he joined the U.S. Army, but was not sent to Europe because of his German origins. Bemelmans became an officer and was promoted to Second Lieutenant. He writes of his experiences in the Army in the book, My War With the United States. In 1918, Bemelmans became an American citizen.

In the 1920s, Bemelmans tried to become an artist and painter while working at hotels, but had substantial difficulties. In 1926, he quit his job at the Ritz-Carlton in New York to become a full-time cartoonist. Bemelmans' cartoon series The Thrilling Adventures of the Count Bric a Brac was dropped from the New York World after six months. He associated with Ervine Metzl, a commercial artist and illustrator who is variously described as Bemelmans's friend, agent, and ghost artist.

In the early 1930s, Bemelmans met May Massee, the children's book editor at Viking Press, who became a sort of partner. Bemelmans began to publish children's books, beginning with Hansi in 1934. He published the first Madeline book in 1939; after being rejected by Viking, it was published by Simon & Schuster. The book was a great success. Bemelmans did not write a second Madeline book until 1953, when he published Madeline's Rescue. Four more books in the series were subsequently published while he was alive, and one more was published posthumously in 1999.

Up until the early 1950s, the artistic media Bemelmans worked in were pen and ink, watercolor, and gouache. As he describes in his autobiographical My Life in Art, Bemelmans had avoided oil painting because it did not permit him to produce artistic pieces quickly. However, at this point in his life, Bemelmans wanted to master the richness of oil painting. To this end, he set out to buy a property in Paris that would serve as a serious, full-blown art studio. In 1953, Bemelmans fell in love with a small bistro in Paris, La Colombe [fr] in the Île de la Cité, and bought it, intending to convert it into a studio. He painted murals therein, but the project was a disaster owing to French bureaucracy, and after two years of frustration and disappointment, Bemelmans unloaded it by selling it to Michel Valette, who converted it into a notable cabaret.

Bemelmans also wrote a number of adult books, including travel, humorous works, and novels, as well as movie scripts. The latter included Yolanda and the Thief. While spending time in Hollywood, he became a close friend of interior decorator Elsie de Wolfe, Lady Mendl.