Peerage is a Technology in Age of Empires III that can be researched at the Capitol building for a price of 1000 food. The upgrade increases hero (i.e., the Explorer) hitpoints by 1000 and the attack by 100%.

The Knighthood upgrade must be researched before this technology becomes available.

Capitol technologies
Blockade | Spies | Knighthood | Peerage | Immigrants | Large Scale Agriculture | Deforestation | Excessive Taxation | Legendary Native Warriors