The Magician's Nephew
"The Magician's Nephew" seems to have been the most challenging Narnia novel for Lewis to write. The other six "Chronicles of Narnia" books were written between 1948 and 1953, "The Magician's Nephew" was written over a five-year period between 1949 and 1954. He started in the summer of 1949 after finishing "The Lion, the Witch and the Wardrobe", but came to a halt after producing 26 pages of manuscript and did not resume work until two years later. This may be as a result of the autobiographical aspects of the novel, as it reflects a number of incidents and parallels very close to his own experiences.