Cotton is one of 31 Rare Resources in the game and available from the beginning. It appears as a brown-white field representing a cotton plantation. Like all rare resources on land, cotton can be obtained by sending a Merchant from the Market to the resource location. Cotton provides the following benefits:
Note: Despite the description, Cotton actually increases the current production progress by 25%. This is equivalent to a production time reduction of 20%, not 25%.The decrease in production times can be quite significant, especially when playing a more combat-oriented game, effectively allowing you to field five units in the regular time of four. Most infantry has a regular base production time of ~15 seconds per unit, thus is created at least (see below) 3 seconds faster. Cavalry units (regularly 15–20 seconds) gets a decrease by 3–4 seconds, ships (regular 12–24 seconds) by 2.5–5 seconds. Note, that production times for combat units ramp up (like resource cost) with each unit of the same type the nation already has.Great Sahara, African Watering Hole, etc).
Originally cultivated in Persia and India, cotton eventually spread east and west through contact with Islam. While not having the same prestigious status as silk, cotton had a probably greater social and historical significance: it was more readily available, and it was easier to wash than wool and silken textiles, and could also be used to form quilted armor which was useful against projectiles such as arrows and darts in combination with other forms of armor.