Under the Spreading Chestnut Tree: The Story of Orwell's 1984 (formerly Before 1984) is an ongoing timeline by Roberto el Rey which gives an interpretation of the backstory to George Orwell's classic dystopian novel Nineteen Eighty-Four. The story is told through a mix of primary sources and narrative sequences, and it is generally updated at least once a week. You can read it here.
Index of Chapters & Parts
Note: Each Part is composed of several entries. Chapters are single posts.
POD: The Shot That Doomed the World
Part 4. A Shifting of Strategies
The Marvelous Misadventures of Eric Blair, Chapter 1
Part 5. There Once Was a Man Named Goldstein...
The Marvelous Misadventures of Eric Blair, Chapter 2
Part 7. The First Seeds of Ingsoc