How did Athens build a new empire?

Answer 1

There was no Greek empire. It never existed. The closest Greece ever came to an empire was during the exploits of Alexander the Great but everything fell apart after Alexander' death. Greece was a collection of independent city-states who only united in the case of a severe crisis and when the trouble was over they went back to their former independent governments.

After the death of Alexander the great, Greece did not become a just collection of city-states. A number of kingdoms were formed. What was left of Alexander's conquests was partitioned, creating the Kingdom of Pergamon (in western Turkey), the Seleucid Empire (Syria, Mesopotamia, and part of Turkey) and the Ptolemaic Kingdom (Egypt and parts of Turkey). The Kingdom of Macedon in mainland Greece was formed as part of the partition. The kingdoms outside Greece were ruled by Greeks and it was this that led to the Hellenistic period, the period when Greek influence spread in the Middle East and Egypt.

In Greece the Kingdom of Macedon was the largest and the dominant state. It covered northern and central Greece. It was this kingdom which the Romans fought in the four Macedonian Wars. There was also the Kingdom of Epirus, which covered the west of Greece.

There were two alliances of Greek groups of city-states: the Aetolian League in southern-central Greece and the Achaean League in the Peloponnese (in southern Greece). These military alliances made these two groups of city-states important military forces. There were formed for defence against Macedon and against Sparta respectively. Sparta and Athens remained important city-states.