The Wizard of Oz, by L. Frank Baum (1900). Page 128:
“The Cowardly Lion was much pleased to hear that the Wicked Witch had been melted by a bucket of water, and Dorothy at once unlocked the gate of his prison and set him free. They went in together to the castle, where Dorothy’s first act was to call all the Winkies together and tell them that they were no longer slaves.
“There was great rejoicing among the yellow Winkies, for they had been made to work hard during many years for the Wicked Witch, who had always treated them with great cruelty. They kept this day as a holiday, then and ever after, and spent the time in feasting and dancing.
“‘Don’t you suppose we could rescue them?’ asked the girl, anxiously.
“‘We can try,’ answered the Lion.
“So they called the yellow Winkies and asked them if they would help rescue their friends, and the Winkies said that they would be delighted to do all in their power for Dorothy, who had set them free from bondage.”