When Knighthood Was in Flower is the debut novel of American author Charles Major written under the pseudonym, Edwin Caskoden. It was first published by The Bobbs-Merrill Company in 1898 and proved an enormous success. According to the New York Times, in its third year on the market the book was still selling so well that it was #9 on the list of bestselling novels in the United States for 1900. The book spawned an entire industry of historical romantic novels and films. In 1901, playwright Paul Kester wrote the Broadway play and by 1907 When Knighthood Was in Flower was still being printed by the reprint publisher, Grosset & Dunlap, when the film rights were sold to Biograph Studios. Set during the Tudor period of English history, When Knighthood Was in Flower tells the tribulations of Mary Tudor, a younger sister of Henry VIII of England who has fallen in love with a commoner. However, for political reasons, King Henry has arranged for her to wed King Louis XII of France and demands his sister put the House of Tudor first, threatening, "You will marry France and I will give you a wedding present - Charles Brandon's head!"

This book is included in Project Gutenberg.