The Clan McDuck is a fictional Scottish clan of cartoon ducks from which Disney character Scrooge McDuck is descended. Within the Donald Duck universe, the clan is related to the American Duck family through the marriage of Hortense McDuck and Quackmore Duck, Donald and Della Duck's parents, giving both of them partial Scottish ancestry. Clan McDuck was created by American comic book author Carl Barks, who also created the character of Scrooge McDuck. Barks' 1948 story "The Old Castle's Secret," in which Scrooge and his nephews search for hidden treasure in McDuck Castle, introduced the backstory of the clan. Other authors built on Barks' work, most notably Don Rosa in his 12-part comic saga The Life and Times of Scrooge McDuck (1992–94) which introduced Scrooge's immediate family. Literary origins In the early 1950s, Carl Barks was in his second decade of creating comic book stories starring Donald Duck and his various relatives. He had personally created several of the latter, including cousin Gladstone Gander and uncle Scrooge McDuck, although the specific relationships between them were still uncertain. To better define these relationships, Barks created a version of the McDuck/Duck/Coot family tree for his own personal benefit, incidentally creating several additional characters. During his retirement, Barks' stories remained popular and gained him unexpected fame. Barks gave several interviews during which he answered questions about his stories and the characters he had created. In 1981, Barks described his personal version of Donald's family tree, which was used by amateur artist Mark Worden in drawing the family tree and including portraits of the characters mentioned. Worden's tree was first published in several fanzines, and later in the Disney-licensed Carl Barks Library, a ten-volume hardcover collection of Barks' stories in black-and-white. In 1987, Don Rosa, a long-time fan of Carl Barks and a personal friend of Mark Worden, started creating his own stories featuring Scrooge McDuck. His stories contained numerous references to older stories by Barks as well as several original ideas. After several years he gained a fan base of his own. In the early 1990s, the Egmont Group, the publishing house employing Rosa, offered him an ambitious assignment: he was to create the definitive version of Scrooge's biography and a family tree to accompany it. The project was intended to end decades of contradictions between stories which caused confusion to readers. The project was to become The Life and Times of Scrooge