War was pretty much constant as the Byzantines fought the Persian-Sasanian Empire and then various Islamic empires. Trade in valuable agricultural land that yielded high taxes meant that the Byzantine Empire was, like the Western Roman Empire, exceptionally rich, and it was slightly more compact as a territory than its predecessor and much more urban, containing, as it did, all of those once-independent Greek city-states, which made it easier to administer. Also, like their Western counterparts, the Byzantines enjoyed spectacle and sport. Chariot races in Constantinople were huge, with thousands turning out at the hippodrome to cheer on their favorites. Big bets were placed and there was a huge rivalry, not just about sports, but also about political affiliations, between the two main teams, the Blues and the Greens. Thanks for putting us on the Greens, Thought Bubble. That rivalry was so heated that riots often broke out between them, and in one such riot, an estimated 30,000 people were killed.