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The Iroquois prepare for war! You get a Shipment of Mantlets. You get 1 Mantlet for every 2 minutes the game has lasted.
—In-game description

Iroquois Morning Wars is a technology in the vanilla Age of Empires III that can be researched at a Trading Post built on an Iroquois settlement. Once researched, one Iroquois Mantlet for every two minutes the game has passed, up to 30 minutes (for a total of 15 Iroquois Mantlets), will appear in the Home City shipment point.

Iroquois Morning Wars was replaced by Huron Trade Dominance in The WarChiefs, which has a similar function.