7. Space Marines
The poster boys of Warhammer 40,000 are surprisingly weak in Dawn of War, even though they theoretically have some of the best units in the game. However, their problem is that they take a long time to get there.
Your units cost more than others and require upgrades to keep up properly. Additionally, you rely on vehicle support to win battles. However, you can only get vehicles starting from Tier 2.
The strength of the Space Marines lies mainly in the late game. Once the Astartes have reached their full strength, they can sweep away almost anything. In 3v3 or 4v4, you are therefore significantly stronger than in smaller match-ups.
Dawn of War offers you the opportunity to play different chapters of the Space Marines. In the game itself, this has no effect and is purely cosmetic, but if you are interested in the lore behind it, you can find the strongest chapters of the loyal Space Marines from Warhammer 40,000 in the power ranking.