Final answer:
The Greeks expanded from the Greek peninsula in search of arable land due to population increases and the poor, rocky soil of Greece after the Dark Age. Greek colonies were established across the Mediterranean for farming and trade. Victories such as those in the Persian Wars bolstered Greek confidence, which also fueled exploration and colonization.
Step-by-step explanation:
The forces that propelled the Greeks to keep moving outward from the Greek peninsula even after they occupied it were manifold. Firstly, the end of the Dark Age saw a population increase, resulting in emigration to accommodate the population that the poor, rocky soil of Greece could not support. Greek colonies were established as far as Spain, the coasts of the Black Sea, North Africa, and on Mediterranean islands such as Sicily, driven by the need for arable land for cultivating crops such as olives and grapes, and for trading opportunities.
Moreover, during the Archaic period, the shortage of farmland led to dramatic changes, with Greeks founding colonies—each becoming an independent polis with equal division of land amongst its citizens—which promoted the idea of civic equality and participation in governance. Additionally, historical migrations in the wake of events like the Trojan War, and movements of the Sea Peoples, contributed to the spread of Greeks and their culture. The Greek victory in the Persian Wars further emboldened the Greeks and united them in pride and confidence about their civilization, propelling further exploration and colonization.