The county of Luxembourg (originally Lützelburg), extending between the Meuse and Moselle rivers and including the Luxembourg province of Belgium, was one of the largest fiefs in the Holy Roman Empire. John of Luxemburg, king of Bohemia and father of Emperor Charles IV, made Luxembourg a duchy in 1354. The elder line of the house continued in Bohemia and other parts of the Roman empire, with Emperors Wenceslaus and Sigismund; the younger line, descended from Charles's brother, Duke Wenceslaus, continued in Luxembourg. (The French noble family of Luxembourg was descended in collateral line from an early count of Luxembourg.)
In 1443, Philip the Good of Burgundy seized the duchy, and in 1451, he was confirmed in possession by the estates of Luxembourg. Luxembourg passed in 1482 to the house of Hapsburg following the death of Mary of Burgundy. For the ensuing three centuries it shared the history of the S Netherlands (see Netherlands, Austrian and Spanish), passing from Spanish to Austrian rule in 1714. The southern part of the duchy, including Montmédy, Thionville, and Longwy, was ceded to France in the Peace of the Pyrenees (1659). In 1684, Louis XIV of France seized Luxembourg, but he was obliged to restore it to Spain by the Treaty of Ryswick (1697). Occupied by the French during the French Revolutionary Wars, the duchy was formally ceded to France by the Treaty of Campo Formio (1797).
The Congress of Vienna (1814–15) officially made Luxembourg a grand duchy, in personal union through the sovereign with the Netherlands. At the same time, Luxembourg became a member of the German Confederation, and the fortress in the capital was garrisoned by Prussian troops. When in 1830 the Belgians rebelled against William I of the Netherlands, Luxembourg shared in the revolt. Belgium, on gaining independence, claimed the entire grand duchy; it eventually obtained (1839) the major part (i.e., the present Belgian Luxembourg prov.). The remainder, continuing in personal union with the Netherlands as well as a member of the German Confederation, became autonomous and was granted a constitution in 1848.
When the German Confederation was dissolved in 1866, William III of the Netherlands agreed to sell the grand duchy to France, nearly provoking war between France and Prussia. At the London Conference of 1867 the European powers declared Luxembourg a neutral territory; its fortress was dismantled and the Prussian garrison withdrawn. William III died (1890) without a male heir; his daughter Wilhelmina succeeded him in the Netherlands, but Duke Adolf of Nassau, from a collateral line, became grand duke of Luxembourg.
Grand Duke Adolf was followed in 1905 by William IV and in 1912 by Marie Adelaide. In 1914, Germany violated the neutrality of the grand duchy and occupied it for the duration of World War I. Grand Duchess Marie Adelaide abdicated in 1919 in favor of her sister, Charlotte, who married Prince Felix of Bourbon-Parma.
Germany again invaded (May, 1940) neutral Luxembourg in World War II. The grand duchess and her cabinet fled abroad, and a government in exile was established in London. Allied troops liberated Luxembourg in Sept., 1944. Luxembourg entered the United Nations (1946) and the North Atlantic Treaty Organization (NATO) in 1949, and it received Marshall Plan aid.
A constitutional revision (1948) abolished the perpetual neutrality of the grand duchy, a status that in practice had ended with the introduction of compulsory military service (1944–67). In 1958, Luxembourg joined with Belgium and the Netherlands to establish the Benelux Economic Union and became a founding member of the European Economic Community (now the European Union). In 1961, Prince Jean, son and heir of Grand Duchess Charlotte, was made his mother's representative as head of state; she formally abdicated in 1964, and Prince Jean became grand duke.
In 1995 Jean-Claude Juncker of the Social Christian People's party became premier; he succeeded Jacques Santer, who became head of the European Union's European Commission. Juncker resigned in 2013 and new elections were called after a misconduct scandal involving Luxembourg's secret service; Juncker was responsible for the agency's oversight. A recent problem in Luxembourg has been the increasing number of aging citizens and a lack of population growth, both of which affect the economy and have led to a dependence on foreign workers. Grand Duke Jean abdicated in favor of his eldest son, Prince Henri, in Oct., 2000. Constitutional changes in 2008 ended the monarch's power to approve Luxembourg's laws.