In ancient Greece, the Peloponnesian War (431&ndash;404 BC) unfolded as a fierce confrontation between the Delian League, led by Athens, and the Peloponnesian League, spearheaded by Sparta. Historians traditionally divide the war into three distinct phases. The initial stage, known as the Archidamian War, witnessed Sparta launching relentless attacks on Attica, while Athens, leveraging its naval dominance, struck the Peloponnesian coast and quelled dissent within its empire. The Peace of Nicias in 421 BC marked the end of this phase, but ongoing conflicts in the Peloponnese soon jeopardized the agreement.<br /><br />In 415 BC, Athens, undeterred, dispatched a formidable expeditionary force to besiege Syracuse, Sicily&mdash;an ill-fated endeavor resulting in the utter destruction of the entire army by 413 BC. This catastrophic event marked the commencement of the war&#39;s final phase, termed the Decelean War or the Ionian War. Backed by the Achaemenid Empire, Sparta fomented rebellions in Athens&#39; subject territories in the Aegean Sea and Ionia, gradually eroding the city&#39;s empire and stripping it of naval supremacy. The Battle of Aegospotami dealt a decisive blow to Athens&#39; navy, effectively concluding the war, and the city-state surrendered the following year.<br /><br />While Thucydides, a preeminent historian of the conflict, never employed the term &quot;Peloponnesian War,&quot; its widespread modern usage reflects the prevailing Athens-centric perspectives among contemporary historians. Notably, J. B. Bury, a distinguished historian, posits that the Peloponnesians likely termed it the &quot;Attic War.&quot;