Luxembourg's history: a country that outlived its own fortress

How a castle on the Bock made a country

People were on this ground long before anyone had a name for it. The oldest artefacts found in the territory are decorated bones from Oetrange, left in the Old Stone Age more than 35,000 years ago, and traces of Neolithic houses have been dug at Grevenmacher, Diekirch, Aspelt and Weiler-la-Tour from the fifth millennium BC. In the Iron Age the Treveri, a Gaulish tribe, built fortified settlements above the Moselle valley; the largest of them, Titelberg, covers 50 hectares. Rome completed the conquest under Julius Caesar in 53 BC and abandoned Gallia Belgica in 406.

The Franks moved in, and the Northumbrian missionary Willibrord founded the abbey of Echternach in 698, which became a centre of learning and missionary work across the Frankish north. The Treaty of Verdun of 843 placed the area in Middle Francia, then Lotharingia from 855, then the Duchy of Upper Lorraine inside the Holy Roman Empire from 959.

Recorded Luxembourg begins four years after that. In 963 Siegfried, count of the Ardennes, traded ancestral lands to the monks of St Maximin's Abbey at Trier for an old fort on the Bock promontory called Lucilinburhuc, usually translated as "little castle", although modern historians link the name instead to Letze, meaning fortification. What mattered was the rock. The old city sits on a steep outcrop at the confluence of the Alzette and the Pétrusse, and UNESCO describes it as a natural fortification that only needed completing on the west side. That single weak flank is the hinge of everything that follows.

A town grew around the fort. About 1060 Conrad, a descendant of Siegfried, was the first to style himself count of Luxembourg, and by the middle of the thirteenth century the counts had extended their lands from the Meuse to the Moselle, absorbing Bitburg, Arlon, Thionville, Longwy and, in 1264, the rival county of Vianden. Most of it arrived by inheritance, marriage and fief rather than by battle.

Why the House of Luxembourg lost its own duchy

The counts then did something no other dynasty from so small a base managed. Henry VII was crowned Holy Roman Emperor in 1312. His son John the Blind ruled Bohemia as king, founded the Schueberfouer fair in 1340 and died fighting at Crécy in 1346, and he remains the country's national hero. Three more of the house wore the imperial crown: Charles IV, whose Golden Bull of 1356 fixed the constitutional structure of the Empire, Wenceslaus IV, and Sigismund, who was also king of Hungary.

The duchy itself was an afterthought to them. Charles IV raised the county to a duchy in 1354 and installed his half-brother Wenceslaus I as the first duke, and Wenceslaus added the county of Chiny in 1364, taking the territory to its greatest extent. Then the line ran out. Sigismund and Elizabeth of Görlitz both died without heirs, and in 1443 Philip the Good of Burgundy took the city in a surprise attack by night, forcing Elizabeth to cede the duchy. The fortress was never taken by assault in its whole history. In 1443 it changed hands to a night raid that met no opposition, and later sieges won it by starvation rather than by breach.

What followed was nearly four hundred years of rule from somewhere else. The duchy passed with the Burgundian inheritance to the Habsburgs in 1477, and the division of the Habsburg lands in 1555 and 1556 put it under the Spanish branch. Luxembourg took no part in the revolt of the Low Countries against Philip II, stayed with what is now Belgium inside the Spanish Netherlands, and was governed from Brussels.

How the partitions cut the duchy down

The duchy stayed clear of the Thirty Years' War until France entered it in 1635, after which came war, famine and epidemics. For Luxembourg the fighting ended not at the Peace of Westphalia in 1648 but at the Treaty of the Pyrenees in 1659, and the price was the fortresses of Stenay, Thionville and Montmédy with the country around them, ceded by Spain to France. Everything surrendered in that first partition was a fortress or the ground that fed one.

Louis XIV began conquering parts of the duchy in 1679 and completed the job by capturing Luxembourg city in 1684. France handed the duchy back to Spain at Rijswijk in 1697, and the treaties of Utrecht and Rastatt transferred it to the Austrian Habsburgs in 1713 and 1714. Each occupier rebuilt the defences: Vauban extended the works under French rule, and Austrian engineers added exterior forts and cut nearly 25 kilometres of casemates into the bedrock.

French Revolutionary troops took the city in 1795 and the duchy became the département des Forêts. A peasant rising against conscription in 1798, the Klëppelkrich, was put down brutally. At the Congress of Vienna in 1815 both Prussia and the new United Kingdom of the Netherlands claimed the territory, and they settled it by exchange: Prussia took the principality of Orange-Nassau, the Prince of Orange took Luxembourg, and the districts east of the Our, the Sûre and the Moselle, around Bitburg and St Vith, went to Prussia. That was the second partition. The compensation was a title, since the duchy was raised to a grand duchy, and the conditions attached were membership of the German Confederation and a Prussian garrison in the capital.

The third cut came from the other side. Most Luxembourgers joined the Belgian revolution of 1830, and from 1830 to 1839 almost the whole country was administered as a Belgian province, the fortress and its immediate surroundings excepted. The Treaty of London of 1839 gave the predominantly French-speaking west, along with the then Luxembourgish-speaking Arelerland, to Belgium as its own province of Luxembourg. More than half the remaining territory went, and what stayed behind is the 2,586 square kilometres inside today's borders.

The 1839 settlement left a smaller, poorer and largely German-speaking state that had lost its Belgian markets. The grand duke's answer was to put it inside the Prussian customs union, the Zollverein, in 1842, which opened the German market, built the steel industry and paid for a railway network laid between 1855 and 1875. About one in five inhabitants emigrated to the United States between 1841 and 1891.

Why the powers agreed to pull the fortress down

By the time it was finished, the fortress covered about 180 hectares while the city inside it covered 120. It had three successive walls, fifteen forts in the centre and nine more outside them, and 23 kilometres of underground passages linking over 40,000 square metres of bomb-proof space. Prussia garrisoned it from 8 July 1814, before the Congress of Vienna declared it a federal fortress on 9 June 1815 and eleven years before the German Confederation formally took it over on 13 March 1826. Around 4,000 Prussian officers and men were quartered among some 10,000 civilians. A British visitor, Norwich Duff, wrote in July 1819 that the town was governed by the Dutch, garrisoned by Prussians under a prince of Hesse, and considered one of the strongest fortifications in Europe.

The Austro-Prussian War of 1866 dissolved the German Confederation and left the Prussian troops sitting in a fortress that belonged to no federation. Bismarck had hinted to Napoleon III at Biarritz in 1865 that France might have a free hand in Luxembourg in exchange for staying out of the coming war. When the French acted on it, offering William III five million guilders for his grand duchy and receiving his acceptance on 23 March 1867, Bismarck reversed himself under pressure from the nationalist press in northern Germany and threatened war. Napoleon III retreated to demanding only that the Prussian garrison leave. Alexander II of Russia called a conference in London, and Britain was glad to host it, fearing that either power's absorption of Luxembourg would weaken Belgium.

The second Treaty of London, signed on 11 May 1867 by all the great powers, guaranteed the perpetual independence and neutrality of the state. Its price was in the text: the westward and underground fortifications, the ones that made the natural site defensible, were to be demolished and never rebuilt. The Prussians left on 9 September 1867. A country had been kept in existence by being made militarily worthless.

What the demolition gave the city

Dismantling took sixteen years, from 1867 to 1883, and cost 1.5 million francs. It destroyed over 24 kilometres of underground defences and four hectares of casemates, batteries and barracks. The government ran the work itself rather than hand the decommissioned fortress to the city, wanting visible compliance with the treaty and fearing a future Franco-German war. Sales of fortress land paid for the demolition and for the new streets laid across it. The method was rough: sections were blown up, usable stone was carried off by residents, and the rest was covered with earth. An international commission inspecting the site in 1883 found a state that had never done anything like it and had been forced to choose between keeping everything and razing everything.

Luxembourgers of the time read it as a liberation. The fortress had been the most visible sign of foreign control, and its governors had restricted building for two centuries so that nothing would interfere with the fields of fire. Once the corset came off, the city expanded for the first time since the fourteenth century. The military wasteland of the Glacis and the Limpertsberg plateau, where construction had been forbidden, was taken over by gardeners who specialised in roses, and the country was known as the Rose Country through the Belle Epoque. Enough of the walls survived as unusable stone to be inscribed, with the old quarters, on the UNESCO World Heritage list in 1994.

Politics moved with the masonry. The constitution of 1841 had created an assembly of 34 deputies with almost no power, meeting in secret under an absolute monarch; 1848 brought a constitutional monarchy and public sessions; 1856 took most of it back. The revision of 1868, drafted after the declaration of neutrality and independence, restored the annual vote on the budget and taxes.

How the grand duchy came by its own dynasty

Independence in 1867 still left the grand duke's crown on the head of the king of the Netherlands. What separated them was a family agreement signed before either state existed. The Nassau Family Pact of 1783 bound the family's Holy Roman lands, Luxembourg and Nassau among them, by semi-Salic law, under which a woman could inherit only once the male line was extinct. When William III died in 1890 leaving one daughter, the Dutch crown, free of the pact, passed to Wilhelmina, while Luxembourg went to Adolphe, the dispossessed Duke of Nassau and head of the Nassau-Weilburg branch. After nine centuries the country had a dynasty that ruled nothing else.

A separate identity had been assembling for decades. The Catholic Church supplied part of it, with a diocese from 1840 and a separate bishopric from 1870, and the Luxemburger Wort grew into the dominant newspaper on the strength of those links. Language supplied the rest. Bilingualism was the norm, but Luxembourgish was what local literature and folklore were written in while French served for diplomacy and law. Writers such as Nicolas Ries pressed it towards literary status, and the Education Law of 1912 made it a compulsory school subject and confirmed it as a separate language. By then emigration had reversed into immigration.

What the German occupations did to the language

How the first occupation unseated a grand duchess

German troops crossed the border in 1914 in violation of the neutrality the great powers had guaranteed in 1867. The government stayed in place and the country was never annexed, and that was the problem: official neutrality under occupation looked to much of the population like collaboration, particularly since many Luxembourgers had gone to fight in the French army. Grand Duchess Marie-Adélaïde abdicated in favour of her sister Charlotte in 1919, and a referendum held months later settled the constitutional question, with 80% voting to keep the dynasty. The same voters chose an economic union with France by 73%, and France declined, so the government negotiated with Belgium instead and signed the Belgium-Luxembourg Economic Union in 1921. The constitutional revision of 1919 introduced universal suffrage. Luxembourg joined the League of Nations on 16 December 1920, having been forced out of the German customs union by the Allies at the end of 1918.

How a census answered the annexation

The second invasion came at 04:35 on 10 May 1940, carried out by the 1st, 2nd and 10th Panzer Divisions, and the capital was occupied before noon. Total Luxembourgish losses that day were 75 police and soldiers captured, six police wounded and one soldier wounded. The government and Grand Duchess Charlotte left, obtained visas in Bordeaux from the Portuguese consul Aristides de Sousa Mendes, and reached the United States by way of Lisbon; Charlotte broadcast to the country through the BBC for the rest of the war.

Germany annexed Luxembourg into the Gau Moselland in August 1942 and justified the act by asserting that its inhabitants were ethnically and linguistically German. A census taken in October 1941 had already answered that argument. Asked their current citizenship, their mother tongue and their ethnicity, an overwhelming majority wrote "Lëtzebuergesch" three times, an episode still called dräimol Lëtzebuergesch. French was banned, so people revived obsolete Luxembourgish words to avoid speaking German, and the language came out of the occupation stronger than it went in.

Forced conscription was declared on 30 August 1942 and answered by a general strike from 1 to 3 September that stopped the administration, agriculture, industry and education. It was one of very few mass strikes against the German war effort in western Europe. The occupiers executed 21 strikers and deported hundreds to concentration camps. Of an estimated 3,500 Jews living in the country before the war, between 1,000 and 2,500 were murdered. Some 13,000 men were called up into the German army and 2,848 of them died in it. American forces entered the capital on 10 September 1944, the Ardennes offensive took back much of the north for a few weeks, and the Germans were expelled in January 1945. Out of a pre-war population of 293,000, 5,259 Luxembourgers died.

Why the country gave up its neutrality

The post-war Chamber revised the constitution and repealed the neutral status that the great powers had imposed in 1867 and that two armies had walked through. Luxembourg helped draft the United Nations Charter adopted on 25 June 1945, entered the Benelux customs union in 1948, signed the Brussels Treaty the same year and became a founding member of NATO on 4 April 1949. Guaranteed by everyone and defended by no one, the state chose alliances instead.

How Luxembourg became one of Europe's capitals

The decisive night was 24 to 25 July 1952. After eighteen hours of negotiation, the Luxembourgish foreign minister Joseph Bech proposed that the High Authority of the European Coal and Steel Community begin work in Luxembourg, and its first officials moved into an office building on the place de Metz vacated by the railways. The seat stayed until the executives of the three communities merged in 1968. Robert Schuman, whose 1950 plan produced the Community, was born in Luxembourg to a French father and a Luxembourgish mother. In the negotiation of the Treaties of Rome in 1957 the government secured the principle of legal equality for every state however small.

The institutions then took a larger piece of ground than the fortress had held. A public fund was created in 1961 to urbanise 360 hectares of the Kirchberg plateau, twice the area of the old works. The Alcide De Gasperi tower, opened in 1966, was the country's first skyscraper. The Court of Justice has been on Kirchberg since 1973, the year the Schuman building gave the European Parliament its first purpose-built chamber, and the Parliament's secretariat has been officially seated in the city since 1992. More than 14,000 people work for European bodies in Luxembourg, among them the Court of Auditors, the European Investment Bank, the Publications Office and Eurostat.

The clearest inversion of the country's history happened on a boat. The Schengen Agreement was signed on 14 June 1985 aboard the MS Princesse Marie-Astrid on the Moselle, at the point where Luxembourg, France and Germany meet, and a second agreement setting out the legal procedures followed at the same spot on 19 June 1990. A state cut down three times because of where its borders lay gave its name to the abolition of checks at them. Luxembourg bought the ship back in 2021 to turn it into an exhibition space.

What replaced the steel the country lived on

The Zollverein had built an economy on the iron ore of the Red Lands in the south, and steel dominated industry until the 1960s. The sector's crisis, from the mid-1970s to the late 1980s, came close to pushing a one-industry country into recession. A tripartite committee of government, employers and unions kept it from turning into open conflict, which is where the phrase "Luxembourg model" comes from. Finance, which had begun to matter from the late 1960s, filled the gap, and thirty-five years later a third of tax revenue came from it.

The country the walls once enclosed has changed shape again. The law of 24 February 1984 made Luxembourgish the national language, alongside French for legislation and all three languages in administration and the courts. In 2025 there were 681,973 permanent residents, 47% of them foreign nationals, the largest group Portuguese. Asked in a referendum in June 2015 whether non-Luxembourgers should vote in legislative elections, the electorate said no, and the revised constitution in force since 1 July 2023 states that the vote may be extended by law to non-Luxembourgers except in those elections. In February 2020 Luxembourg became the first country to make public transport free nationwide.