Amazon
Amazons are a race of warrior-women from Greco-Roman myths. Though they only appear in a handful of myths, they have stuck in the imagination of nerds everywhere due to the strange fondness /tg/ has for aggressive, take-charge women who can kick major ass.
The Amazons are believed to have been inspired in real life be Grecian encounters with the Scythians, nomadic tribes of horseback archers who often included female archers and even full-fledged warriors in their ranks, something highly exotic to the very patriarchal Greeks and even more patriarchal Romans who shamelessly stole most of the Grecian culture for themselves in later years.
Amazons appear all over the place in fantasy, and even science fiction, with their treatment varying widely, often in response to how grimdark their setting is. They may be just a human tribe, they may have advanced magic and/or technology, or they may be borderline monstergirls with supernatural prowess elevating them above men. Likewise, they may allow men to share their territory but women are clearly in charge (or at least do the fighting), they may enslave men, they may just not let men get anywhere near them on a permanent basis. They may even be a one-gender race, to emphasize their inhumanity.
Amazons often show up as a female warrior class in RPGs, especially Japanese ones. They may have either a ranged focus (the mythical Amazons were said to be expert archers), or they may be powerful melee fighters.
Dungeons & Dragons
Aside from being an obvious culture to include in a magical realm, Amazons have had several encounters with Dungeons & Dragons.
Way back in Greyhawk Adventures, Amazons were actually statted up as a unique monster race, essentially treated as a culture of female human, elven, dwarven, gnomic or halfling barbarians. They can be seen here, if you're feeling curious or nostalgic: http://www.lomion.de/cmm/humaamaz.php
Mongoose Publishing includes an Amazons book as part of their notorious Slayers Guide To X series, with the usual somewhat dodgy quality.
Amazon Class
Diablo II: Diablerie, a Wizards of the Coast cash-in for Diablo II, includes the Amazon class as part of the five translations of the base game's classes. It's a ranged specialist fighting class, favoring the use of bows and spears, and designed to reach level 25, with the following traits.
Chief Ability Scores: Dexterity (primary), Wisdom and Charisma Hit Die: D10 Class Skills: Craft (Any, Bowyer, Fletcher), Disable Device, Heal, Knowledge (Religion), Listen, Move Silently, Search, Spot, Wilderness Lore Skill Points: 2 + Int modifier, multiplied by 4 for the first level Weapon & Armor Proficiency: All weapons, all armor, shields Saves: Good Fortitude save, poor Wisdom and Reflex Attacks: 2 attacks at level six, 3 attacks at level eleven, 4 attacks at level sixteen, 5 attacks at level twenty-one, 6 attacks at level 25 Attack Bonus: Great (primary attack bonus equals Amazon levels) Feats: It gains 9 feats between levels 1 and 24 Ability Increase: +1 Ability score every 4 levels
The Amazon's key class features are its ability to select Amazon Abilities. Starting at level 1, it gets one ability each level, except when it gains an Ability Increase. The level after it gains an ability increase, it gains access to the next tier of Amazon Abilities - so Tier 2 at level 5, Tier 3 at level 9, etc. There are six tiers of Amazon Abilities all told.