The Roman conquest of the Achaean League, as recounted in the Federalist, is the final collapse of a Greek confederacy whose internal dissensions make it vulnerable to outside powers. Rome enters the conflict at the league’s invitation, defeats Macedon, and then fosters division among the Greeks until their union is broken and Achaia is subjected to Roman rule. The episode supplies a stark political lesson: a confederation may be undone by weakness among its members as surely as by power at its head.

Background: A League Under Pressure

The Achaean League had sought to resist Macedonian influence while contending with tensions among Greek states. After Cleomenes, king of Sparta, attacked the Achaeans, they faced a choice between submission to him and seeking assistance from Macedon, their former oppressor. They chose the latter. A Macedonian army arrived and defeated Cleomenes, but the victory brought dependence rather than security: the league’s most compliant terms secured only permission to continue exercising its laws.

Philip’s later tyrannies prompted a renewed Greek coalition. The Achaeans, weakened by internal dissension and the revolt of Messene, were joined by the Aetolians and Athenians in opposition. Still unable to prevail, they again sought foreign military aid, this time from Rome. Their appeal opened the way for a powerful neighbor to intervene in Greek affairs.

Roman Intervention and the League’s Disintegration

Rome accepted the invitation and defeated Philip, bringing Macedon under its power. The victory was followed by a new crisis within the league: dissensions broke out among its members, and Rome encouraged them. Callicrates and other popular leaders became instruments for turning their fellow Greeks against the union.

Rome proclaimed universal liberty throughout Greece, then used the members’ pride in their sovereignty to draw them away from the league. The argument against union thus became a lever of division: Rome represented the league itself as an infringement on the independence of its members. In the Federalist’s account, this strategy tore apart what it calls Greece’s last hope of liberty. The resulting weakness left Rome little difficulty in completing through force the ruin its political arts had begun; the Achaeans were defeated, and Achaia was placed under Roman domination.

Consequences and Political Meaning

The conquest is presented not as an isolated defeat but as the culmination of a chain of failures. The league’s internal disputes and the revolt of one member diminished its capacity to resist; recourse to foreign arms gave a stronger power entry into Greek affairs; and Rome’s encouragement of discord converted member-state sovereignty into an instrument against collective action. The earlier appeal to Macedon had already shown the danger of relying on a victorious ally, and the recourse to Rome repeated that pattern on a more destructive scale.

The episode supports the Federalist’s broader comparison of confederacies. Its lesson is that their characteristic danger lies in anarchy among the members rather than tyranny in the federal head. The account contrasts the nominal preservation of separate sovereignty with the practical loss of collective independence: once the league was divided, Rome could complete its conquest. The Roman victory therefore functions as a warning about disunion, foreign intervention, and the vulnerability of a political union that cannot hold its members together.