The Frisians have a long history of fighting — against Romans, Franks, Vikings, Hollanders, and occasionally each other. For a people often described as peaceful farmers and traders, they spent a surprising amount of time at war. Here are the major conflicts that shaped Frisian history.
The Revolt Against Rome (28 AD)
The first recorded Frisian war was their revolt against the Roman Empire in 28 AD. The Roman tax collector Olennius had raised the tribute demanded from the Frisians to unreasonable levels. The Frisians rebelled, killed Roman soldiers, and besieged a Roman fort. When the Roman general Lucius Apronius marched north to crush them, the Frisians inflicted heavy casualties. The historian Tacitus records roughly 1,300 Roman soldiers killed. Emperor Tiberius decided not to retaliate further, and the Frisians effectively won their freedom for decades.
The Frankish-Frisian Wars (7th–8th Century)
The longest and most consequential Frisian conflict was their on-and-off struggle against the Frankish Empire. In the late 7th century, Frisian king Radbod fought the Franks for control of the Rhine delta region, including the important trading town of Utrecht. Radbod initially had success, recapturing Utrecht and pushing back Frankish influence. But after his death around 719 AD, the Frankish mayor of the palace Charles Martel launched a series of devastating campaigns against the Frisians. The decisive moment came at the Battle of the Boarn in 734, where Charles Martel defeated King Poppo and killed him. After this, Frisian independence crumbled, and the territory was incorporated into the Frankish Empire. Forced Christianization followed.
Viking Raids (9th–10th Century)
After coming under Frankish rule, Friesland was hit hard by Viking raids from the 830s onward. The great trading center of Dorestad was raided repeatedly between 834 and 863. Viking leaders like Rorik of Dorestad were actually granted Frisian lands as fiefs by the Frankish emperors in an attempt to stop the raids — essentially paying the Vikings to protect the coast from other Vikings. This period devastated the Frisian economy and effectively ended the Frisians’ role as the dominant trading power of the North Sea.
The Battle of Warns (1345)
One of the most celebrated moments in Frisian military history came in 1345, when a large army from the County of Holland invaded Friesland. The Hollanders, led by Count William IV, landed near the village of Warns on the Frisian coast. The Frisian farmers and militia fought back and routed the invading army. Count William IV was killed in the fighting, along with many of his knights. The battle became a powerful symbol of Frisian resistance and independence. It’s still commemorated annually at the Warns monument.
The Arumer Zwarte Hoop (1515–1523)
In the early 16th century, a Frisian guerrilla army known as the Arumer Zwarte Hoop (the Black Heap of Arum) fought against Saxon and Habsburg control of Friesland. Led by the legendary Pier Gerlofs Donia (known as Grutte Pier, or “Big Pier”), this rebel force attacked occupation troops and raided ships. Grutte Pier became a folk hero — stories describe him as an enormous man who wielded a massive sword that no ordinary person could lift. After his death in 1520, the rebellion continued under other leaders but was eventually crushed. It was the last major armed Frisian resistance movement.
After Grutte Pier
After the 16th century, Friesland became part of the Dutch Republic and later the Kingdom of the Netherlands, and the era of independent Frisian warfare came to an end. Frisians continued to serve in Dutch armies and navies, but they fought as part of a larger state rather than as an independent people. The military history of the Frisians is essentially the story of a small coastal people who punched above their weight for over a thousand years before finally being absorbed into something bigger.
