War of the Blue Divide

Named after the body of water separating them, the War of the Blue Divide pitted the Summerset Isles against their former ally Valenwood. After a vicious but short war, Summerset defeated Valenwood, gaining several coastal islands as a result of the war. The most notable damage from the war was when the Altmer destroyed many of Valenwood's harbors. The war occurred soon after Valenwood’s war with Elsweyr, meaning Valenwood was in an already weakened state. The war took an even worse turn, however, when the Khajiit took advantage of Valenwood's further distress, reigniting the war and forcing the Wood Elves to fight on two fronts.

The only known episodes concerning the war were when, in 3E 396, the Bosmer Parikh tribe began their rampage through southeastern Valenwood against other tribes, receiving aid from Summerset itself. It is unknown whether or not this was the cause of the war.