From the 15th to the 18th century, but especially in the 16th century, Oudenaarde was a world-known centre of tapestry production. The town's name, meaning “old field”, still lingers on in “outnal”, an obsolete English term for a kind of brown linen thread.
The history of the current municipality of Oudenaarde starts in 974, when Otto II, Holy Roman Emperor and King of Germany, built one of its three fortifications on the Scheldt at Ename to protect his kingdom against possible attacks from Francia (the other two frontier posts were at Valenciennes and Antwerp). Ename grew very fast. By 1005, the town already had a couple of churches and had become the largest town in the duchy of Lotharingia. In 1033, Baldwin IV, Count of Flanders took the city as a frontier post against emperor Henry III. In 1047, Baldwin V consolidated his father’s victory by having his wife found a Benedictine abbey there. By that time, the former merchants and guild artisans of Ename had fled across the Scheldt to the recently founded city of Oudenaarde.
In the 11th century, Oudenaarde’s economy flourished, thanks to the proximity of the Scheldt and to the burgeoning, but vibrant cloth and tapestry industry. Churches, cloisters and hospitals were built. Throughout the Middle Ages, the city was one of the staunchest supporters of the Counts of Flanders, defending them against insurrections from the South, and even from Ghent. The city became known as the residence of the nobles. It built itself a flagship town hall (built 1526–1537), which we can still admire today, and the St-Walburga church. Charles V stayed here for a couple of months in 1522 and fathered an illegitimate daughter, Margaret of Parma, who was to become Regent of the Netherlands.
During the Reformation, the people of Oudenaarde chose Protestantism and allied themselves with Ghent against Charles V. In 1582, after a prolonged siege by Margaret's son, Alexander Farnese, the city finally gave in, causing most merchants, workers, and even nobles to flee. Oudenaarde fell under the Counter-Reformation, which for a short while revived the commerce of tapestry. The glory days, however, never came back. The French attacked and took the city three times in less than a century. In 1708, one of the key battles in the War of the Spanish Succession, known as the Battle of Oudenaarde, was fought in the vicinity of the city. Oudenaarde slumbered as a provincial town under the Habsburg regime.
Like its neighbours, in the 1790s it suffered religious curtailment imposed by the French Revolution. The city later suffered damage during World War I, which is commemorated by several monuments scattered around town.
Recurring events include a beer fest in June, an open-air musical festival in the summer, and an agricultural fair in February. The celebrated Tour of Flanders voor Vrouwen, the women's Tour of Flanders cycle race, starts every spring in Oudenaarde. The men's Tour of Flanders has passed through Oudenaarde on several occasions, and regularly ascends the Koppenberg hill in the municipality. The Koppenberg hillside is also used for a November cyclo-cross race.
Every ten years, one of the largest floral displays in Flanders takes place on the market square (Grote Markt). The last one took place in 2005.