Empire of Nicaea

The Empire of Nicaea was the largest of the three Byzantine Greek successor states founded by the aristocracy of the Byzantine Empire that fled after Constantinople was occupied by Western European and Venetian forces during the Fourth Crusade. Founded by the Laskaris family, it lasted from 1204 to 1261, when the Nicaean recovery of Constantinople re-established the Byzantine Empire.
History
Foundation
In 1204, Byzantine emperor Alexius V Ducas Murtzouphlos fled Constantinople after crusaders invaded the city. Theodore I Lascaris, the son-in-law of Emperor Alexius III Angelus, was proclaimed emperor, but he too fled, to the city of Nicaea (today İznik) in Bithynia, realizing the situation in Constantinople was hopeless.
The Latin Empire, which was established by the Crusaders in Constantinople, had poor control over former Byzantine territory, and Byzantine successor states sprang up in Epirus and Trebizond as well as Nicaea. Trebizond...