Resources are the materials that are needed to create units or buildings and to research upgrades in the Empire Earth series. Resources are collected by citizen or fishing boats.
In Empire Earth I
The resources are Food, Wood, Gold, Stone and Iron. Each resource is gathered from various places on the map.
Food can be gathered from foraging patches, hunting wild animals or farming. Farms are the only resource that can be created by the player.
Wood is taken from trees. Each tree contains 500 units of wood.
Gold, Iron and Stone can be mined, and has 300,000 units as a default resource.
In Empire Earth II
There are two types of resources: the main resources which are available in all epochs, and the special resources, which become available only in certain epochs.
Food, Wood, Gold and Stone are the main resources, while the special resources are the Tin, Iron, Saltpeter, Oil and Uranium.
For the special resources, each of them is gathered according to the epoch the player is in currently, Tin becomes available in Epochs 1 through 6 and can be mined. Iron becomes available through Epochs 4 through 9 and can be mined, too. Saltpeter becomes available in Epochs 7 through 12 and can also be mined. Oil becomes available in Epochs 10 through 15; however, the player must build Oil Derricks and garrison citizens to gather the resource. Uranium becomes available in Epochs 13 through 15, but instead of building Oil Derricks, the player has to build Uranium Mines and garrison citizens to gather the resource.