A white peace is a type of peace treaty where nations agree to a cessation of hostilities and a return to the pre-war situation. No territory changes hands, no money is exchanged, and no cores are given up by either side in the peace treaty. A white peace offer must be sent to an enemy which they will either accept or decline. To send a white peace offer, select the enemy nation, click "Sue for Peace", and select the option "White Peace".
After five years of war without battles or blockades an automatic white peace is declared. Besieging, looting and occupying provinces does not count.
Note that territorial changes do not entirely revert to as they were before the war - if colonies were seized by either side during the war, they will remain under the control of the final occupant.