The Eleans' control of Olympia was the defining fact of their history. The sanctuary and its games drew competitors and spectators from across the Greek world, and the Eleans managed this responsibility with a combination of religious authority and political muscle. Athletes were required to arrive in Elis a month before the games and train under Elean supervision — a rule that served both quality control and the city's own economy. The Hellanodikai, the judges of the games, were Elean citizens. Infractions of the Olympic code were their business. The sacred truce, the ekecheiria, which theoretically suspended hostilities for the duration of the games, was enforced — or attempted — by Elean diplomats. This arrangement made Elis a place of perpetual importance to the Greek world, even when its military power was limited. When the Spartans once excluded the Eleans from the games in 420 BC for violation of the truce, it was a serious blow to Elean prestige — and it shows how central that prestige was to their identity.

The region of Elis — a fertile lowland watered by the rivers Peneus and Alpheus, whose name may be cognate with the English word 'valley' — was inhabited from early times but did not coalesce into a unified polis until 471 BC, when the scattered communities of the region synoikized, merging into a single city-state centered on the city of Elis. Evidence from early inscriptions suggests the community was practicing some form of popular self-governance by around 500 BC — scholar Eric W. Robinson has argued this makes Elis one of the earliest democracies in Greece. The literary sources mention a democratic revolution in 472 BC. The classical democratic government functioned through a popular Assembly and a Council that began with 500 members and grew to 600 by the end of the fifth century BC. Public officials called demiourgoi submitted regularly to public audits — a degree of accountability that was remarkable for its time. The district of Koile Elis, the largest of three regional divisions, was famous in antiquity for its cattle and horses.

Elis had its intellectual side. Hippias of Elis was a sophist known to Socrates and Plato, appearing in two of Plato's dialogues. Phaedo of Elis, one of Socrates' companions and present at his death, founded the Elean School of philosophy. Most famously, Pyrrho of Elis founded Pyrrhonism — the philosophical tradition of radical skepticism, the suspension of judgment on all matters — after traveling with Alexander the Great to India and encountering Indian ascetic philosophers. Elis also produced Coroebus, recorded as the first victor at the ancient Olympic Games. Against these distinctions must be set an ancient joke: the musician Stratonicus of Athens called the Eleans the greatest barbarians — barbarotatoi — in Greece, and ancient lexica list them among barbarophones, speakers of unintelligible Greek. The Elean dialect, a form of North-West Doric, is indeed one of the most challenging for modern readers of ancient inscriptions.

The modern village of Elis, with a population of around 150, sits 14 kilometers northeast of Amaliada, built directly over the ruins of the ancient city. Excavations began under the Austrian Archaeological Institute between 1910 and 1914, and continued from 1960 to 1981 under the Archaeological Society of Athens. The ancient theater, built in the fourth century BC, survives as one of the best-preserved in Greece — it had a capacity of 8,000 people, and below its foundations archaeologists have found graves dating to the Early Helladic, sub-Mycenaean, and Protogeometric periods, testament to habitation stretching back thousands of years before the great Olympic franchise was established. The finds from these excavations are displayed in the local archaeological museum, which opened in 1981 and moved into a new building in 2003. The plain around the site remains agricultural, green and quiet, crossed by the same rivers that the Eleans' cattle and horses once drank from.