The Irish name Loch Coirib derives from an earlier form, Loch Oirbsean. According to the placename traditions of medieval Ireland, Oirbsen was another name for Manannan mac Lir, the Tuatha De Danann figure who served as a god of the sea. The lake bears his name. In modern Irish it is also called An Choirib, the Corrib. The wider lake basin and significant adjacent areas of woodland, callows grassland, and raised bog have been incorporated into the Lough Corrib Special Area of Conservation. The lake itself was designated a Ramsar site in June 1996, recognising its international importance as a wetland habitat. The northern basin is deeper, the southern shallower, with the two halves connected by a narrow channel near the village of Cong.

Since 2007, a local surveyor and cartographer has been creating up-to-date charts of Lough Corrib using modern sonar equipment. The work has uncovered objects of major archaeological significance. The Annaghkeen Boat, found by the survey, is 40 feet in length and intricately carved, a Bronze Age or Iron Age dugout canoe of a quality rarely seen elsewhere in Ireland. The Carrowmoreknock Boat is a well-preserved tenth-century vessel that went down carrying three Viking battle axes, frozen in time at the moment of sinking. The wreck of a Victorian pleasure yacht represents a more recent vintage. The Underwater Archaeology Unit of the National Monuments Service investigates each find. All historic wrecks in the lough are now protected, and any dive on them requires a licence. The lake's bed is, in archaeological terms, a continuous record of more than three thousand years of human use.

On a small rocky island in the upper lough, between Maam and Doon, stands Hen's Castle, in Irish Caislean-na-Circe, a fortification of the medieval O'Connors and O'Flahertys. The castle's most famous resident was Grainne O'Malley, known as the pirate queen of Connacht, who lived during the reign of Elizabeth I and controlled the waters around Clew Bay and the lakes of the interior with a fleet she commanded personally. In 1225, the Lord Justice ordered Odo O'Flaherty to surrender the castle to Odo O'Connor, King of Connaught, as security for his loyalty. Grace O'Malley used it three centuries later as one of her bases. The castle still stands on its rock, accessible only by boat, exposed to whatever weather the lough sends. Cruise boats from Cong, Ashford Castle, Galway City, and Oughterard pass it daily.

Midway between Cong and Oughterard lies Inchagoil Island, one of the largest of the wooded islands in the lough. It holds two churches: one dedicated to Saint Patrick and a twelfth-century structure known as the Saints' Church. The island shows evidence of an early monastic settlement, and tradition holds that Saint Brendan of Clonfert spent time on an island in this lake after returning from his transatlantic voyages. Paths wind around Inchagoil. An old cemetery sits in the woodland. The remains of four or five cottages stand where families once lived on the island full-time, before isolation drove them to the mainland. Views from the island take in the Maumturk Mountains, Joyce Country, and the Twelve Bens of Connemara, the whole sweep of western Connacht visible from a 30-acre wooded island in the middle of a 176-square-kilometre lake.

In 1867, William Wilde published Lough Corrib, its Shores and Islands, a comprehensive antiquarian study of the lake's archaeology, history, and topography. Wilde, a leading surgeon as well as a serious historian, built a summerhouse on the lough's banks called Moytura House. His son Oscar Wilde spent boyhood summers there. The book was a thorough work, much of it still cited by modern researchers, but it was also a personal record of a man's attachment to a particular body of water. Paul Feval's 1846 novel La Quittance de minuit is set near Lough Corrib, and Pat O'Shea's 1985 children's novel The Hounds of the Morrigan drew its inspiration from the unspoilt countryside around the lake. The 2009 drama Nothing Personal was filmed in part at Moytura. The lake keeps appearing in stories told about it.