1930: Tales of A Basque Grandmother

Here's a book published in 1930, thus entering the public domain on January 1 2026:

Tales of A Basque Grandmother
by Frances Carpenter
(illustrated by Pedro Garmendia)
Internet Archive

Frances Carpenter [1890-1972] was a folklorist and children's book author, most famous for her "Grandmother" series. This is the first of the "Grandmother" books to enter the public domain; we will have to wait for the rest — Tales of a Russian Grandmother published in 1933, Tales of a Chinese Grandmother published in 1937, Tales of a Swiss Grandmother published in 1940 and Tales of a Korean Grandmother published in 1947. You can find out more about Carpenter's life and work at Wikipedia.