The Roman conquest of Britain effectively began with the expeditions made by Julius Caesar in 55 BCE. The actual conquest itself was a gradual process - beginning in 43 CE with the invasion led by Emperor Claudius. All of these emperors contributed except for the Emperor Constantine who ruled two centuries after the Roman conquest of Britain was completed.

Justinian I is the most famous ruler of the early Byzantine Empire. He reigned from 527 to 565 CE. Justinian is often remembered for his famous legal code, called the Code of Justinian. He also was notable for his attempts to reunite the fractured Roman Empire. During his reign the Byzantine Empire expanded significantly, due to Justinian’s reconquest of many lands which had previously been held by the Western Roman Empire.

Alexander the Great lived from 356 BCE until 323 BCE. In this relatively short amount of time he conquered one of the largest land empires in human history - stretching from Greece and Egypt in the west all the way to India in the east. Alexander the Great was the leader of the Macedonian Empire, Macedonia is a region that borders Greece to the north.

The Qin were able to take shape so quickly in part due to their ability to build on the precedents set by the Xia, Shang, and Zhou dynasties. The Qin had already developed a bureaucracy, aristocracy, well-equipped army, stable agricultural output, and a growing population. On the other hand, the Roman empire was essentially starting from scratch in the creation of its empire. Both the Qin and the Romans had centralized governments, brutal military forces, and attractive urban cultures.

Persia was known for its unapproachable monarchs and elaborate imperial centers. Greece was known for its extent of popular participation in politics. Rome was known for its well-trained army and relentless expansion. China was known for being built off tradition and being highly centralized.

Alexandria was once the capital of Ptolemaic Egypt - it was the capital of Egypt during its Hellenistic period from approximately 300 BCE until 30 BCE Alexandria was a global centre of learning and commerce and contained the famous Library of Alexandria.

Octavian, later called Augustus Caesar, founded the Roman Empire after he defeated his rivals from the Second Triumvirate in 27 BCE.

These are all Pharaohs who ruled during the period of Egyptian history known as the New Kingdom. This was a period of Egyptian military conquest and expansion and some of these rulers, notably Ramesses II, are known for their extensive territorial conquests. Hatshepsut, it is worth noting, was the first female ruler in recorded human history.

The Indian subcontinent was effectively united (excluding modern-day Tamil Nadu and parts of Kerala) under the Mauryan Dynasty by Ashoka the Great in the third century BCE. Ashoka was a great military commander, but also a notable proponent of religious tolerance.

In the third century CE the Roman Empire experienced a series of disastrous civil wars that led the Emperor Diocletian to believe that the empire was too large for any one centralized government to administer. He divided the empire into a tetrarchy - four distinct, but united provinces. This division would lead to the formation of the Eastern Roman Empire and the Western Roman Empire.