Thoughts prompted by flipping through various AD&D books in just the right order.
In AD&D 1e, rangers don't have two weapon fighting.
In AD&D 2e, they do. Drizzt is, I think, commonly cited as the source. But where did Drizzt's two weapon fighting come from?
It was Unearthed Arcana that introduced the Drow as an official PC race. And as Unearthed Arcana (p. 10) notes:
Dark elves do not gain the combat bonuses of the surface elves with regard to sword and bow, but may fight with two weapons without penalty, provided each weapon may be easily wielded in one hand.
This ability may have precedents in the D series of modules or other sources (Dragon?). Anyone know?
So here's what I'm seeing. A two weapon wielding dark elf ranger who is an exile from his homeland (see UA p. 10, again) is a legitimate starting character type in AD&D, via Unearthed Arcana. The books take off, people dig Drizzt, and the two weapon fighting thing gets transferred/associated with the character class (ranger) rather than the race (dark elf) in a lot of people's minds. AD&D 2e makes it official. From 3e (3.5, especially) on, it is generalized even more, leading to weapon styles, which are especially numerous in Pathfinder.
Maybe you already knew this. I just realized it (assuming I'm getting the major lines of descent right).
The literary inspiration for the original D&D ranger was Strider.
Now it's Drizzt.
Modern D&D -- Ouroboros or Oedipus?