Just about any of the official (and canonized) Assault maps in 2004 are recreations of historical feats:
In AS-BP2-Acatana, the attacking team takes the place of a group of Skaarj Marauders who infiltrate a research facility protected by a dangerous asteroid field and advanced defense systems in order to steal some blueprints.
In AS-BP2-Jumpship, the attacking team takes Izanagi's raiding team's place with the objective to hijack a jumpship developed by Liandri scientists which allows them to jump into any space without the need of a jumpgate. As of Unreal Tournament III, which takes place way after 2004, this jumpship is still in Izanagi's hands.
AS-BP2-SubRosa has the attacking team taking the place of an N.E.G. raiding group which storms the headquarters at Liandri with the objective to uncover the truth about some blueprints.
In an inversion of "you play as the Empire, your enemy is the Resistance", AS-BP2-Thrust recreates the storming of an N.E.G. facility at the hands of an anti-N.E.G. group who managed to destroy a rocket sending it half-fueled and directionless.
In AS-Convoy, the attacking team takes the place of an N.E.G. squad on their mission to recover some prototype missiles from a group of Hellions.
AS-FallenCity has the attacking team once again in the N.E.G. side raiding a rebel outpost surrounded with heavy anti-aircraft protection.
AS-Glacier is another chapter of the Corporation wars. A strike force backed by Axon raided an Izanagi base and stole a prototype Ion Plasma Tank. The base itself? It was guarded by both Izanagi soldiers and the N.E.G. elite force, composed by some guys going by the name of "ThunderCrash".
AS-RobotFactory has an elite squad of Liandri's best soldiers finishing a robot uprising on a mechanical asteroid by destroying its manufacturation facility and the AI generator.
DM-Rankin, by far, the most played map of UT2004. It helps a bit that both maps were available since the first demo.
ONS-Torlan, also from 2004, which also received an official remake for Unreal Tournament III. And in 5 different flavours, to top it all. It also has the distinction of being the most played Onslaught map of the game. And for good reasons.
Malcolm was presented in 2003 as the reigning, nine-time champion of the Tournament. Come 2004 and Gorge managed to strip him off the title.
As usual, several of the Tournament combatants' have impressive feats in their careers:
Scarab's description:[He's] A Lieutenant in the Desert Legion and veteran of three tribal wars. (...)
Gkublok's description:Gkublok was named "Walking Death" by the Nali during his stay on Na Pali.
Outlaw's description:Outlaw was recruited into the Hellions after he reputedly went on a cross-galaxy crime spree in which he murdered nearly 300 civilians.
Karag's description:Before joining the Iron Guard, Karag honed his weapon handling skills during a long stint as a Marshall for the Terran Colonial Authority.
The returning characters are all acknowledged as in-universe badasses:
Lauren's description:Born into a poor asteroid miner family, she became notorious by stealthily eradicating her parents' competitors in space before becoming a full time Tournament warrior.
Xan's description:Former Tournament champion Xan Kriegor is an almost mythical figure. His return from several years of isolation has been greeted with great trepidation by other Tournament competitors.
Malcolm's description:Needs no introduction - most famous veteran of the Tournaments, recognized on every planet.
Kragoth's description:Known as the 'Star Slayer,' Kragoth is a dread Necris Phayder assassin. He is rumored to have single handedly killed the entire crew of an ICV Star Cruiser.