Why did Rome split into two different empires?

Related questions

1. How did Constantinople's name change over 1100 years later?
2. When did the Byzantines lose Italy?
3. Who built Istanbul?
4. When was the Byzantine Empire most powerful?
5. Why did Constantinople become Istanbul?
6. When did the Byzantine Empire start and end?
7. What did Constantinople become?
8. How does Orthodox Christianity differ from Roman Catholicism?
9. How is the Byzantine Empire different from the Roman Empire?
10. Was Constantinople a Roman city?

Tags

1. #halves
2. #diocletian
3. #constantinople
4. #later
5. #longer
6. #feasible
7. #western
8. #eastern
9. #governed
10. #govern
11. #central
12. #divided
13. #roman
14. #provinces
15. #empire
16. #grown
17. #emperor
18. #byzantium