Attempt to pull off a successful rendition of Warhammer 40k, and succeeds with flying colours.
Dawn of War, when it came out 4 years ago, was revolutionary. It was the first squad based rts game that I encountered, and the fact that it was based on Warhammer 40k had a direct link with my hobby at the time. To see the armies that I had spent so much time painting, modelling and fighting with come to life was incredible for me.
The game itself is based on 4 armies: The Space Marines, The Chaos Space Marines, The Orks, and The Eldar. In the campaign mode, you can only play as the Space Marines, which was disappointing for me as a Chaos supporter. A further downside to the campaign, is that it feels more like a tutorial system than a campaign, preparing yourself for the skirmish maps. In that guise, the campaign does admirably, however, in the sense of an actual campaign, it is somewhat disappointing in its simplicity.
The armies themselves are nicely varied, as they should be. Drawing on the depth of forces available to tabletop gamers, the people at Relic did admirably in creating four distinctly varied, yet well balanced forces. Each army works to an individual's prefered fighting style. The Eldar for your agile quick strike player, the Orks for your "drown them in a tide of bodies" player, the Space Marines for your standard, well rounded simplicity player, and Chaos for....well.....the guy who likes spikes, psychopathic killers and ravaging daemons.
The variations between Dawn of War and every other rts game on the face of the Earth (upon its release) lie in the gameplay itself. Like I said, squad based combat, for one. You no longer have one ork hitting one human with his axe. Now you have a squad of 16 orks throwing themselves at a group of 8 superhumans with machine guns and electrically powered armour. Another variation is the resource gathering scheme. No longer can you sit back while your peons harvest gold and wood in the safe comfort of your base. In order to generate Requisiton (the primary resource) you need to venture out of your base and capture Strategic Points, Critical Locations, and Relics, placed around the map. This style inevitably throws you into conflict with your enemies fairly quickly, as you both attempt to capture the same point.
Critical Locations are used in some Skirmish Scenarios in the same way as "King of the Hill", capture and hold half of the Critical Locations on the map for a certain amount of time to win. Relics act as a key to each race's superweapon, and inevitably become a hotbead of fighting, as you attempt to secure them for your own good, while stopping your opponents from acquiring their superweapon.
All in all, Dawn of War is one of the best RTS games out there. It also stands as more or less the only proof (even now) that somebody CAN make a good game based on the world of Warhammer 40k. For those reasons, I give it a 9.