The Perhappsy Chaps was Thompson's first published book and came out in 1918, the same year as the first Raggedy Ann book. The stories originally appeared on the children’s page of the Philadelphia Public Ledger, a weekly newspaper feature written by Thompson. On the right is a blurb that ran in a November 1918 issue of the Ledger, advertising the newly published book version of the poems.
Thompson's second book was The Princess of Cozytown, which wasn't published until 1922. This was a collection of fairy tales by Thompson, some of which had previously been published in St. Nicholas magazine. Apparently the book was already pending publication when she was contracted to continue the Oz series, and had her first Oz book published in 1921.