Aslan creates Narnia in C.S. Lewis’s The Magician’s Nephew.
Published in 1955, The Magician’s Nephew is the sixth Narnia novel in publication order but the first in the series’ internal chronology. The story follows Digory Kirke and Polly Plummer, whose travels through magical worlds bring them to the moment when Narnia is formed.
Aslan sings Narnia into existence, and his song brings the landscape, plants, and animals to life. The scene also establishes the lion as the creator and governing spiritual figure of the Narnian world. Digory and Polly witness this creation, while the arrival of Jadis foreshadows the danger that later affects Narnia.
Readers sometimes answer Digory because he is the viewpoint character in the creation story, or Uncle Andrew because his experiments help initiate the journey. Neither creates the world. Aslan is the character who performs the act of creation.