There's been much ado about the proper order to read The Chronicles of Narnia, and here's a totally-not-boring history lesson on why. When the Chronicles were originally published, they were released in this order without a numbering system:
When a numbering system was added to the Chronicles, it was in that order. Eventually, Harper Collins and Lewis's executor, Walter Hooper, decided to change the order to match the chronological order, citing letters Lewis wrote to fans supporting the decision to read them that way. The new standard became:
Since then, the proper way to read the Chronicles has become a huge issue among fans, leading them to do what fans do best: choosing sides and duking it out. If we had to pick a favorite argument though, it would be Alan Jacobs's. Jacobs points out that the stories were not revised to fit the new order. So when the narrator says "the children in The Lion do not know who Aslan is 'any more than you do'" it doesn't make much sense if you've already read The Magician's Nephew. You'd know oodles about Aslan in that case.
Then what's the proper way to read the Chronicles? Whichever way works best for you, really. Good arguments have been made for each case, and you can't really go wrong as long as you're reading. That whole reading thing is kind of the point in the end anyway. (Source)
Throughout this guide, we sometimes call Peter, Susan, Edmund, and Lucy "the Pevensie children." But careful readers might have noticed that not once in Prince Caspian are these four referred to by that name. In fact, unless you have an edition with supplemental material, the surname Pevensie never appears once in the novel. It may seem odd, but the family name of these four super important Narnia characters doesn't appear until the third book, The Voyage of the Dawn Treader—the fifth book if you're reading chronologically. (Source)
C.S. Lewis and J.R.R. Tolkien's friendship is among the legendary BFFs of literary history. Lewis supported Tolkien's fictional endeavors, eventually leading to him creating this place called Middle-earth. Maybe you've heard of it. Likewise, Tolkien helped convert Lewis to Christianity, beginning his fruitful interest in Christian apologetics (source).
But it wasn't all sugar, sunshine, and giggles. According to Norman Stone, director of Shadowlands, these two could bicker with the best of them. And one of the things they fought fiercely over was Lewis's The Chronicles of Narnia. Stone says:
Tolkien thought there were too many elements that clashed: a Father Christmas and an evil witch, talking animals and children. He did not like allegory and thought Lewis's book was too pushy in a Christian sense. (Source)
Remember the scene where Aslan commands Bacchus to tear down the bridge to free the rivergod? You might have noticed a tiny tickle the back of your brain while reading it, and that tickle is Tolkien's ghost grumbling from beyond the grave.
Despite our initial wishes, Caspian the Conqueror is not the current heavyweight champion of the Narnia Wrestling Entertainment (or NEW). Instead, he's Caspian's great(x7) grandfather, and the Telmarine king who first conquered Narnia.
Lewis probably based this bit of Narnian history on real world conqueror of Britain, William the Conqueror. William was a Norman king who ruled in the 11th century. Believing himself the rightful heir to the British throne, he invaded the country in 1066 and claimed victory on Christmas Day that same year. Much like the Telmarines, the Normans took control of the country's government and religion, ousting many of the natives who had previously held powerful positions.
There's a famous tapestry called the Bayeux Tapestry that depicts William's invasion up until the Battle of Hastings. Some clever fellows have animated the Tapestry's illustrations and added subtitles to tell the story. It's totally worth checking out, and you can find it right…here. (Source)