Luxembourg, a small landlocked state between Belgium, France and Germany, lies where the plateaux of the Ardennes meet the valley of the Moselle, and people have lived in its land since Ice Age hunters left flint tools there more than 35,000 years ago. A Mesolithic hunter was buried at Loschbour about 6000 BCE, Linear Pottery farmers settled the loess lands about 5300 BCE, and the Celtic Treveri built their great town on the Titelberg. Caesar's legate Labienus defeated them in 53 BCE, and for four centuries the country was part of the Roman province of Gallia Belgica, around Augusta Treverorum (Trier), a residence of emperors from 293. When Rome withdrew, the Franks came, and in 698 the Anglo-Saxon missionary Willibrord founded the abbey of Echternach.

On 12 April 963 Count Siegfried exchanged lands with the abbey of St Maximin in Trier for the small fort of Lucilinburhuc on the rock of the Bock above the Alzette, and from this exchange the history of Luxembourg is dated. His house gave the empire a queen, Kunigunde, and the countess Ermesinde, who ruled for fifty years, granted charters of freedom to Echternach in 1236 and to the town of Luxembourg in 1244. Her descendant Henry VII was crowned emperor in 1312, John the Blind became King of Bohemia and died at Crécy in 1346, Charles IV was crowned emperor in 1355 and raised Luxembourg to a duchy in 1354, and Sigismund, the last of the line, ended the Western Schism at the Council of Constance. In the night of 21–22 November 1443 Burgundian troops took the city by surprise, and the duchy passed to the Habsburgs, who ruled it from Brussels as part of the Netherlands.

For three centuries Luxembourg was a Catholic frontier province, loyal to Spain in the Dutch Revolt and ravaged by plague and war, which lost Thionville and other southern districts to France in the Treaty of the Pyrenees of 1659. Louis XIV besieged the fortress in 1684, and Vauban rebuilt it as the “Gibraltar of the North”, which Spanish, French and Austrian engineers filled with the casemates below the Bock. After the French capitulation of 1795 the country became the Département des Forêts, rose in the Klëppelkrich of 1798 and received the Napoleonic Code. The Congress of Vienna made Luxembourg a grand duchy in 1815, held by the King of the Netherlands, a member of the German Confederation with a Prussian garrison in its federal fortress, and the Belgian Revolution cost it its western half in the Treaty of London of 1839. After the Luxembourg Crisis the powers guaranteed the perpetual neutrality of the country in the Second Treaty of London of 1867 and ordered the fortress dismantled; the Thomas process of 1879 gave the iron ore of the south a new use, and steel made a poor farming country industrial.

When William III died in 1890 the personal union with the Netherlands ended and the Nassau-Weilburg line took the throne with Grand Duke Adolphe. Germany occupied the neutral country in 1914–1918, and Grand Duchess Marie-Adélaïde gave way to her sister Charlotte in 1919, the year of universal suffrage and of a referendum that confirmed the monarchy. The Wehrmacht overran Luxembourg on 10 May 1940, the Gauleiter Gustav Simon tried to Germanise it, and the general strike of August 1942 answered forced conscription; the government and the grand duchess carried on in exile, the country was liberated in September 1944, and the Battle of the Bulge devastated the north that winter. After the war Luxembourg gave up neutrality, joined Benelux, NATO and the United Nations, and became a seat of European institutions from 1952, a financial centre, the home of RTL, SES and ArcelorMittal, and the place where the Schengen Agreement was signed in 1985. It adopted the euro in 1999, Jean-Claude Juncker led its government from 1995 to 2013, a new constitution entered into force in 2023, and Grand Duke Guillaume V succeeded his father Henri on 3 October 2025. Explore the ten ages below through selected events from the timeline.