The document summarizes key events in ancient Greek history during the 5th century BC. It describes the height of Athens' power during the Golden Age under Pericles' leadership. However, resentment grew among Athens' allies over its growing empire. This led to the Peloponnesian War between Athens and Sparta. Though Athens was initially successful, a devastating plague and failed military campaigns weakened it. Sparta gained the upper hand, ultimately defeating Athens and dismantling its empire in 404 BC.