​The Eastern Roman Empire became known as the Byzantine Empire. It was at its most powerful in the a.d. 500s. The empire stretched east to Arabia, south to Egypt, and west to Italy.

​Constantinople was the capital of the empire. The location of the city gave it special advantages. The city sat on a peninsula between the Black Sea and the Aegean Sea. It was surrounded on three sides by water. This made the city easy to defend. Because the city sat between Europe and Asia, it became a crossroads for trade. Merchants from far away did business there and trade grew. Constantinople became the wealthiest part of the Roman Empire.

​People called Constantinople the “New Rome.” Many wealthy Romans moved there. The city had many Roman-style buildings, including an outdoor arena for sporting events. It was called the Hippodrome. Like Rome, officials gave free food and entertainment to the poor.

​People from many lands settled in the Byzantine Empire. Their different customs blended together to form a new culture. Of all the groups who made up the population, the Greeks were the largest. Over time, the empire became less Roman and more Greek. Most Byzantines spoke Greek, so officials and emperors learned to speak Greek too. Between a.d. 500 and a.d. 1200, the Byzantines developed one of the most advanced civilizations in the world.

​Justinian’s Rule
Emperor Justinian ruled the Byzantine Empire when it was at its most powerful. He was a skilled general and a strong leader. He controlled the military and made the laws.
Justinian was married to Empress Theodora. She helped Justinian rule the empire. Theodora helped her husband choose government officials. She helped women gain more legal rights. She urged Justinian to grant women the right to own land. This reform helped widowed women earn money to take care of their children.

​When angry taxpayers rebelled in a.d. 532, Empress Theodora's wisdom helped stop the crisis. The people threatened the government. Justinian's advisers told him he should leave the city to be safe. Theodora told him he would not like his life if he ran away. She said he should stay and fight to protect the empire. He took her advice and stayed. Justinian's army stopped the riot and brought order back to the capital. This victory made him a more powerful ruler.

​One of the most important things Justinian did was in the area of law. He ordered a group of scholars to organize the laws and make them simpler and better. The new laws were easier for people to understand and follow. The Justinian Code is still the basis of legal systems in many countries today.

​Many Byzantine emperors ordered workers to build forts, government buildings, and churches all over the empire. The emperors supported the work of artists and architects. Justinian ordered the building of a church called the Hagia Sophia. The Hagia Sophia has gold and silver decoration inside. It is also decorated with mosaics, pictures or patterns made from small pieces of colored glass or stone. This church became the religious center of the empire. It still stands today as a museum.
The Byzantines also became famous for their mosaics. This Byzantine art usually showed figures of saints. Saints are Christian holy people.

​Justinian knew the empire had once been much larger. He wanted his army to be strong so they could take back the lands that had once been part of the empire. He wanted his army to protect the borders of the empire.

​A general named Belisarius reorganized the Byzantine army and made it stronger. He created cavalry—groups of soldiers on horses. The cavalry wore armor and carried bows and long spears. Justinian’s army fought in Italy, Spain, and northern Africa. It conquered the invaders who had taken lands from the Western Roman Empire. The army also defeated the Persians. It was able to secure the eastern border again.

​However, these conquests did not last long. A deadly disease, known as "Justinian's Plague," moved through Asia and Europe. It killed millions of people, including Roman soldiers. There were not enough soldiers to protect the large empire. There also was not enough money to pay them. After Justinian died, the empire again lost control over most of the western lands.