How and when was the Byzantine Empire established:
A Roman emperor called Diocletian, thought that since Rome was in a severe case; political problems, economical problems, social problems, etc... it would be a good idea o split it into 2. The Easter Roman Empire and the Eastern Roman Empire.
After Diocletian splits Rome into two (Eastern & Western Roman Empire, in 286 AD), the Western Empire falls, since all the goods were going to the Eastern Empire. The Eastern Empire became wealthy and was later on then called the Byzantine Empire, while the Western Empire fell to the Barbarians. The Eastern's Empire capital became Constantinople, which is modern day Istanbul. Constantinople was also once called Byzantium, but was later on changed in honor of emperor Constantine I in 330.
After Diocletian splits Rome into two (Eastern & Western Roman Empire, in 286 AD), the Western Empire falls, since all the goods were going to the Eastern Empire. The Eastern Empire became wealthy and was later on then called the Byzantine Empire, while the Western Empire fell to the Barbarians. The Eastern's Empire capital became Constantinople, which is modern day Istanbul. Constantinople was also once called Byzantium, but was later on changed in honor of emperor Constantine I in 330.