Mary Pope Osborne books in order

Mary Pope Osborne (born 1949) is an American children's author best known for the Magic Tree House series, which began with Dinosaurs Before Dark in 1992. She was born at Fort Sill, Oklahoma, on 20 May 1949 and grew up in a military family that moved often.

Osborne studied drama and then religion at the University of North Carolina, graduating in 1971, and worked as a medical assistant, travel agent and assistant editor of a children's magazine before her first book, Run, Run As Fast As You Can (Random House, 1982). The Magic Tree House books follow the siblings Jack and Annie on time-travel adventures; Random House published Dinosaurs Before Dark on 28 July 1992, with illustrations by Sal Murdocca, who drew the American series until AG Ford took over. Books from number 29, Christmas in Camelot, were later renumbered as a separate Merlin Missions series. She writes the non-fiction Fact Tracker companions with her husband, Will Osborne, and her sister, Natalie Pope Boyce. The series had sold more than 134 million copies worldwide by 2017. Osborne has written more than 60 books for children and served two terms as president of the Authors Guild.

For collectors

The Random House first printing of Dinosaurs Before Dark (1992) is the foundation book. British collectors should note that UK editions were retitled: Dinosaurs Before Dark appeared as Valley of the Dinosaurs, The Knight at Dawn as Castle of Mystery and Mummies in the Morning as Secret of the Pyramid, so the American and British firsts carry different titles.