 Complete the following phrase:  The final centuries of the Empire exhibited a general trend of decline. It struggled to recover during the 12th century, but was delivered a mortal blow during the Fourth Crusade, when Constantinople was sacked and the Empire dissolved and divided into competing Byzantine Greek and Latin realms. Despite the eventual recovery of Constantinople and re-establishment of the Empire in 1261, Byzantium remained only one of several small rival states in the area for the final two centuries of its existence. Its remaining territories were 