The barbarian is a character class in Dungeons & Dragons.
For a complete list, see Category:Barbarians.
In Original Dungeons & Dragons, an early precursor to the barbarian was the berserker, a subclass of the fighting-man, in New D&D Character Subclass: The Berserker, Dragon #3 (Oct 1976), p.27 by John Pickens.
AD&D 1st edition
The barbarian was officially introduced in Dragon #63 (Jul 1982) as a fighter sub-class. It returned in Unearthed Arcana (1e) (1985), with an Eastern variation introduced in Oriental Adventures (1e) (1985).
A revised version of the barbarian was introduced in Dragon #148 (Aug 1989).
AD&D 2nd edition
The barbarian returns as a character kit in PHBR1 The Complete Fighter's Handbook (1989), then as a standalone class in PHBR14 The Complete Barbarian's Handbook (1995).
D&D 3rd edition
Barbarians are one of 11 character classes introduced in the Player's Handbook (3.0) (2000), and returning in the Player's Handbook (3.5) (2003).
D&D 4th edition
D&D 5th edition
The barbarian is one of 12 classes appearing in the Player's Handbook (5e) (2014).
At level 3, barbarians select a primal path (subclass) which customizes the class further. The primal paths detailed in the Player's Handbook are the Path of the Berserker and the Path of the Totem Warrior. Additional primal paths include the Path of the Battlerager in the Sword Coast Adventurer's Guide (2015), and the Path of the Ancestral Guardian, Path of the Storm Herald, and Path of the Zealot from Xanathar's Guide to Everything (2017).
The barbarian was created by Gary Gygax. The class was inspired by characters such as Conan the Barbarian.
The first class with the name "barbarian" was published in Games Workshop's White Dwarf #4 (Dec 1977/Jan 1978), created by author Brian Asbury. This was during the time White Dwarf had a standing deal for D&D intellectual properties with TSR in the UK. The class was later updated in White Dwarf #12 (Apr/May 1979).