More than three million children were evacuated from cities in England during WWII to keep them self. Mothers with children under five were evacuated along with many teachers. But most of those evacuated were children. There were sent to live in the countryside to be safe from bombings. (If you know the story of The Lion, the Witch, and the Wardrobe, that’s how the children end up at the professor’s house.)
Think how scary it must have been to have to leave home, to leave your mother, and to go and live with a stranger.
Children were labeled like a package so the trains would know where to take them. They weren’t matched to families, but to communities. Host families would come and look them over and choose which children they wanted to stay with them. Think about being chosen last in such a circumstance!