The peninsula has been inhabited since prehistoric times. Its modern name derives from ancient Greek mythology, specifically the legend of the hero Pelops, who was said to have conquered the entire region. The name Peloponnesos means "Island of Pelops".
The Mycenaean civilization, mainland Greece's (and Europe's) first major civilization, dominated the Peloponnese in the Bronze Age from its stronghold at Mycenae in the north-east of the peninsula. The Mycenean civilization collapsed suddenly at the end of the 2nd millennium BC. Archeological research has found that many of its cities and palaces show signs of destruction. The subsequent period, known as the Greek Dark Ages, is marked by an absence of written records. In 776 BC, the first Olympic Games were held at Olympia, and this date is sometimes used to denote the beginning of the classical period of Greek antiquity. During classical antiquity, the Peloponnese was at the heart of the affairs of ancient Greece, possessed some of its most powerful city-states, and was the location of some of its bloodiest battles. The major cities of Sparta, Corinth, Argos and Megalopolis were here, and was the homeland of the Peloponnesian League. Soldiers from the peninsula fought in the Persian Wars and was the scene of the Peloponnesian War of 431 BC-404 BC. The Peloponnesian War began in 431 BC between the Athenian Empire (or The Delian League) and the Peloponnesian League which included Sparta and Corinth. The war lasted 27 years, with a 6-year truce in the middle, and ended with Athens' surrender in 404 BC.
It fell to the expanding Roman Republic in 146 BC and became the province of Achaea. During the Roman period, the peninsula remained prosperous but became a provincial backwater, relatively cut off from the affairs of the wider Roman world.
SICYONIA. SICYON (SIKYON). Ca. 400-323 BC. Silver AR Stater. 25mm, 12.20gr. BCD Peloponnesos 218; BMC 57. Obv: Chimaera standing left with forepaw raised, ΣE below, wreath in right field. Rev: Dove flying left within wreath. A truly beautiful coin with one of the most fascinating mythological monsters of classical antiquity. NGC AU★ 5/5, 5/5, Fine Style.