Maurice Sendak grew up in the shadow of the Holocaust. Born to Polish Jewish parents a year after the Great Depression began, he was still a child when his parents heard the news that all of their relatives still in Poland had perished at the hands of the Nazis. Sendak's parents were heartbroken, and his mother suffered from depression. Sendak was often sick as a child, too, and spent a lot of time in bed. As a result, Sendak felt that his childhood was dominated by the specter of death. When he wrote Where the Wild Things Are, he gave his protagonist, Max, the precious ability to escape emotional turbulence at home. By the power of his imagination, Max could set himself free.
The somber quality of Sendak's childhood was not the only aspect of his early life that he drew on in order to create Where the Wild Things Are. Sendak told journalists that the inspiration for the wild things themselves—the strange, looming, grotesque monsters of Max's imagination—came from his own relatives. He remembers hating interactions with his relatives as a child. They were immigrants from Poland whose families were dead; who had only just escaped themselves; and who were so clearly, even to a child, haunted by that reality. Apparently Sendak even remembered their favorite line to him and his brother as children—"We'll eat you up"—and incorporated it into Where the Wild Things Are.
