The first partition (1659) – Treaty of the Pyrenees

The Treaty of the Pyrenees concluded the long-running Franco‑Spanish War and marked the rise of France as a dominant European power. Spain gave up key fortresses like Montmédy, Stenay, and Thionville to France after this treaty. Luxembourg lost roughly 1,060 km², or 10% of its territory, too.

The second partition (1815) – Congress of Vienna

After Napoleon’s downfall, European powers met at the Congress of Vienna to redraw the continent’s borders and restore equilibrium. Luxembourg was elevated to a Grand Duchy, placed in a personal union with the Dutch crown, and made part of the German Confederation. Prussia gained strategically important northeastern areas, including Bitburg, Saint‑Vith, Schleiden, and Waxweiler, a loss totalling around 2,280 km², or 24% of Luxembourg’s contemporary territory.

The third partition (1839) – Treaty of London

Following the Belgian Revolution of 1830, much of Luxembourg aligned with Belgium, prompting diplomatic resolution via the 1839 Treaty of London. This resulted in the loss of the western, French-speaking portion, approximately 65% of its territory, to Belgium, becoming what is now the Belgian province of Luxembourg. The remaining rump Grand Duchy, smaller but sovereign, persisted under Dutch rule but gradually embraced its national identity.

The combined effect of the three partitions reduced Luxembourg from approximately 10,700 km² to 2,586 km², with the “lost” territories now parts of France, Germany, and Belgium. This resizing sculpted the geography and politics of modern Luxembourg, leaving behind a resilient, independent duchy.