Final answer:
Pericles led the Athenian Empire during its Golden Age, introducing key democratic reforms. Cleisthenes laid the foundation for democracy, while Socrates, Plato, and Aristotle were philosophers rather than political leaders.
Step-by-step explanation:
The Athenian Empire was led by Pericles, who was a prominent and influential statesman, orator, and general during Athens' Golden Age. It was under his administration that democratic institutions thrived and cultural prosperity reached new heights. Pericles introduced reforms that allowed poorer citizens to occupy public office and even provided a salary for those serving as jurors, strengthening the democratic process.
Cleisthenes is credited with the foundation of democracy in Athens in the late sixth century BCE, setting up the framework upon which leaders like Pericles would build. While Socrates, Plato, and Aristotle are monumental figures in ancient Greek philosophy and intellectual history, they were not rulers of the Athenian Empire.