Siege of Boulogne

The Siege of Boulogne took place from 19 July to 18 September 1544, during King Henry VIII of England's third invasion of France. Henry was motivated by French aid to England's Scottish enemies. In 1543 he allied with Charles V, Holy Roman Emperor, (also King of Spain), whose Catholic allegiances were, for a time, overruled by the political advantages of an alliance against France.

In early 1544, a large English force departed from Calais. Later it split into two parts. One part, under the Duke of Suffolk, moved to the coast town of Boulogne and laid siege to it on 19 July. A few weeks later, Henry arrived to take command of the siege himself. The lower section of the town, fortified lightly, fell quickly to heavy bombardment, which continued through August. By September, the upper town was breached and taken, but the central castle still held out. The French garrison's firepower prevented any approach on foot, so the English dug mines under the castle, and the French surrendered on 13 September.

However, Charles V then made peace with France. The French then attacked in the Second Siege of Boulogne.

Over the following years, neither England nor France found the strength to engage in full-on war with one another. French attempts to retake Boulogne failed, while English attempts to gain more territory around Calais and Boulogne also failed. Henry awaited a large French invasion fleet which never came, and subsequently much of the military resource during his and his son's reigns was diverted to war in Scotland.