Julia Louise Gage Carpenter (1851 – 1931) was the sister of Maud Gage Baum and sister-in-law of L. Frank Baum. Baum borrowed details from the life of the Carpenter family when he wrote The Wonderful Wizard of Oz. Julia Gage Carpenter kept a diary of her homesteading experience, which has been used by scholars and historians as a source for the subject. Julia and Magdalena Carpenter were the witnesses for Baum's last will and testament.