Oudenaarde means old field in Dutch - a name that survives obscurely in English as outnal, an archaic word for a kind of brown linen thread. The municipality includes thirteen villages around the city core, among them Ename, Eine, Melden, and Mater. Local history reaches back to 974, when Otto II, Holy Roman Emperor, built one of his border fortifications on the Scheldt at Ename to defend his kingdom against attacks from Francia to the west. Ename grew faster than anyone expected. By 1005 it was the largest town in the Duchy of Lotharingia, with multiple churches inside its walls. Then Baldwin V, Count of Flanders, seized it in the 1040s, and his wife Adele of France founded the Benedictine abbey of Saint Salvator in 1062 to demilitarize the site. The merchants and craft guilds of Ename simply crossed the Scheldt and helped found Oudenaarde on the other bank, where their commercial energies could keep flowing under different lords.

In the eleventh century the new city flourished on the cloth and tapestry trade. Throughout the Middle Ages Oudenaarde was a stubborn supporter of the counts of Flanders, defending them against Ghent itself. The reputation that endured longest was for tapestry: from the fifteenth through the eighteenth centuries, but especially the sixteenth, Oudenaarde was one of the great European centers of the art, its weavers second only to Brussels. The wealth produced the flagship town hall built between 1526 and 1537, the UNESCO-listed Brabantine Gothic masterpiece on the market square. Just a few years before construction began, in 1522, Emperor Charles V spent some months in Oudenaarde - and fathered an illegitimate daughter, Margaret of Parma, who would grow up to become Regent of the Netherlands. The double-headed Habsburg eagles carved over the town hall's attic windows are an oblique tribute to that visit.

During the Reformation, Oudenaarde sided with Protestant Ghent against Charles V, and paid for the choice. In 1582 it fell after a long siege by Alexander Farnese, the son of Margaret of Parma - the same Margaret born here a half-century earlier - and most of its merchants, weavers, and even nobles fled. The Counter-Reformation revived the tapestry trade for a while, but the glory days never returned. The French army took the city three times in less than a century, prompting Sebastien le Prestre de Vauban to upgrade its fortifications during the brief French occupation. Then on 11 July 1708, the city's name went into the textbooks of European military history. The Battle of Oudenaarde, fought just north of the city during the War of the Spanish Succession, was a decisive victory for the Duke of Marlborough and Prince Eugene of Savoy over the French army of Louis XIV. It is still studied at staff colleges. Two centuries later, in October and November 1918, Oudenaarde found itself on the front line again, this time as the American 37th and 91st divisions fought to cross the Escaut in the final weeks of the First World War.

Oudenaarde today is best known for two things its industrial cousins cannot easily copy. The first is Oud Bruin - Old Brown - a sour, complex beer style sometimes called Flanders Brown, aged in bottle for months, fermented over weeks by yeasts and bacteria. The Liefmans Brewery in town is the most famous producer. The second is the Tour of Flanders. The men's race has been finishing in Oudenaarde since 2012, and the women's Tour of Flanders starts here every spring. The Koppenberg, a brutal cobbled climb nearby, first appeared in the race in 1976 and was removed after the chaotic 1987 edition, then restored and reintroduced in 2002 following road improvements. The Koppenbergcross cyclo-cross race takes place on the same hillside. The Centrum Tour of Flanders museum on the Markt commemorates the event year-round. Notable Oudenaarders include the painter Adriaen Brouwer, who portrayed peasants drinking in low taverns; the cyclist Mario De Clercq, a three-time world cyclo-cross champion; and Charlotte Vandermeersch, the actress and filmmaker. The Church of Our Lady of Pamele on the banks of the Scheldt, begun in 1234, and the Church of Saint Walburga near the market complete the historic core.