My buddy +Torben Schau identified 10 books that influenced him, and asked me to list 10 books that influenced me.
This was hard, because I have, by my estimation, read at least 4000 books in my life (based on 3 books/week since I was 8 years old, rounded down to account for re-reads). I did finally come up with a group of 10 books that I found very influential. I listed them in no particular order, because really, it's hard to categorize "influential."
1. Deadhouse Gates – Steven Erikson.
This book remains my single favorite fantasy novel. And I've always loved fantasy, so basically this is my favorite book of the 4000 or so I've read. For me it is the perfect blend of worldbuilding detail, adventure, war, tragedy and heroism. If I ever, as a writer or DM, come up with characters as great as the ones introduced in this book, I will be happy forever. For Malazan fans, this is where we first meet (and sometimes, say goodbye to): Icarium, Mappo Runt, Coltaine, Bult, Duiker, Lostara Yil, FUCKING KHARSA ORLONG, Leoman of the Flails, S'ormo Enath, Stormy, Gesler, Heboric Light Touch and Baudin Younger. I did that list from memory. Man, what a great book.
2. The Lord of the Rings – J RR Tolkien
Stuff like The Hobbit and the Gammage Cup introduced me to fantasy, but Tolkien's masterpiece really nailed down my love for the genre. The part where Aragorn tells the hobbits that Weathertop used to be known as Amon Sul, and that that Elendil watched from the Tower for the arrival of Gil-galad before the Last Alliance set out to wage war against Sauron gives me the chills every time I read it. The FIRST time I read it I was about 10 or so, and all I could think was "WHO ARE THESE PEOPLE AND HOW DO I LEARN MORE ABOUT THAT?" Tolkien, as much as any writer, influenced my deep love for history, and my affection for those striving against vast odds.
3. Voltaire’s Bastards – John Ralston Saul
One of the non-fiction books on the list. I read Voltaire's Bastards when I was living in Australia, and it blew me away. His deconstruction of how a series of logical "rational" decisions can lead to terrible consequences has stuck with me my entire life. I still try to work backwards from the desired outcome when making decisions, so this book definitely had an abiding impact.
4. The Watchmen – Allan Moore
A comic. Possibly THE comic. This book made me realize you could get as much, or more, out of a comic/graphic novel as you could out of a traditional novel. Ozymandias is very much Voltaire's Bastard, so I'm not surprised those two works come very close together. Plus, it's the most brilliant deconstruction of the Superhero you're ever going to read. All comics look different after you read The Watchmen, and if that isn't influential, I don't know what is.
5. The Book of Three – Lloyd Alexander
This book would be classified as Young Adult now, and I know I read it when I was around 8 or 9. It was scary, mythic, tragic and ultimately triumphant, and ignited my love for Celtic/Welsh mythology. The Huntsmen and Arawn have both featured in my RPG campaigns, and the tone and themes of The Book of Three have been influential in my gaming since forever.
6. The Judging Eye – R Scott Bakker
If Tolkien ignited my love for fantasy, R Scott Bakker and Steven Erikson brought it to a full burn. I really liked the Prince of Nothing, but the Judging Eye absolutely blew me away. The Second Apocalypse series is a modern re-imagining of Lord of the Rings, and read comparatively, it's quite a ride. To me, Lord of the Rings is 3rd edition D&D, and The Judging Eye is DCC run by Rob Zombie. Amazing, amazing book.
7. The Illiad – Homer
I have a degree in Greek and Roman Studies, and the Illiad is a huge part of why. My dad had a copy of the Richard Latimore translation, and I read it in high school. The clashing of the armor and the roaring of the armies as they smash together has stuck with me 'lo these many years, and I still love the doomed hero (and no, I don't mean Achilles, he's an asshole).
8. Snow Crash - Neal Stephenson
The only science fiction book on the list. Glossolalia, a main character NAMED Hiro Protagonist, swordfighting, computers, virtual reality, an Eskimo badguy with knives made of glass and a personal nuke? Stephenson taught me that a story can have all kinds of weird shit in it, but if it's awesome, none of that matters. And Snow Crash is awesome. It set my baseline for sci fi and futuristic novels.
9. The Deluxe Transitive Vampire – Karen Gordon
The other non fiction book. It's about grammar. And it's funny and clever and excellent. What more needs to be said?
10. Aztec – Gary Jennings
Aztec is a Gary Jennings book. So. If you know Gary Jennings, that says quite a bit. It's got sex, violence, more sex, extremely graphic violence, oh, and really well researched history. I generally feel that you learn history better from high-quality historical fiction than any history textbook, and Aztec is pretty much WHY I feel that way. Also, it has quite a bit of sex. Books can have sex, in fact, I would argue that they mostly should.