"Aggressive" is a leader trait. Civilizations led by an Aggressive leader get a free 
Combat I promotion for all melee and gunpowder units. In addition, they get a production bonus of +100% for Barracks and Drydocks.
In Warlords and Beyond the Sword the following leaders are Aggressive:
Alexander (
Greek)
Boudica ( Celtic)- Genghis Khan ( Mongolian)
- Hammurabi ( Babylonian)
- Kublai Khan ( Mongolian)
- Montezuma ( Aztec)
- Ragnar ( Viking)
- Shaka ( Zulu)
- Stalin ( Russian)
- Tokugawa ( Japanese)
In vanilla Civilization IV, the following leaders are Aggressive:
- Alexander ( Greek)
- Genghis Khan ( Mongolian)
- Huayna Capac ( Incan)
- Kublai Khan ( Mongolian)
- Montezuma ( Aztec)
- Napoleon ( French)
- Tokugawa ( Japanese)
| Civilization IV Leader traits [edit] |
|---|
| Aggressive • CharismaticW • Creative • Expansive • Financial • ImperialisticW • Industrious • Organized • Philosophical • ProtectiveW • Spiritual |
| W Added in Warlords |