Byzantine Empire and Ottoman Empire

The Byzantine Empire, also known as the Eastern Roman Empire, was the continuation of the Eastern part of the Roman Empire centred on Constantinople during late antiquity and the Middle Ages. Having survived the fall of the Western Roman Empire in the 5th century AD, it endured until the fall of Constantinople to the Ottoman Empire in 1453. The term 'Byzantine Empire' was coined only after its demise; its citizens used the term 'Roman Empire' and called themselves 'Romans'.

The Ottoman Empire, also known historically as Turkey or the Turkish Empire, was a state that spanned much of Southeastern Europe, West Asia, and North Africa from the 14th century to the early 20th century, centred in modern-day Turkey. It also controlled parts of southeastern Central Europe between the early 16th and early 18th centuries.