What is now Luxembourg was controlled by a variety of peoples and powers in ancient times, through the Middle Ages, and into the modern era.

One of the first of the well-known of those were the Treveri, a Gaulish tribe mentioned in the Gallic Commentaries of Julius Caesar. The Romans found the Treveri more cooperative than many of their Gallic neighbors, two revolts notwithstanding, and the Treveri lands existed relatively tranquilly within Gallia Celtica and then Gallia Belgica.

Next on the scene were the Franks, and then came the Merovingians and Carolingians. The landmark Treaty of Verdun, in 843, placed the former Treveri lands in Middle Francia, which became Lotharingia. In the 10th Century, the ruling entity was the Holy Roman Empire.

What many historians say was the birth of Luxembourg proper was the erection of Luxembourg Castle in the second half of the 10th Century by Siegfried I, count of Ardennes. The original name of the site is often written as Lucilinburhuc, although other spellings (notably Lutzburg and Lichtburg) populate some historical accounts. The castle begat a fort, which begat a supporting town; the result, on a strategic high point known as the Bock, was a prized fortress known for years as the "Gibraltar of the North."

Ruling this land were a series of Counts, as they termed themselves. Succeeding Siegfried from the House of Ardenne-Luxembourg were his son, Henry I; Henry I's nephew, Henry II; Henry II's brother, Giselbert; that count's sons, Conrad I and Henry III; Henry's brother, William I; and William's son, Conrad II. That count's death with no heirs led to a long interlude of rule by Conrad II's cousin, known as Henry the Blind. His death, in 1196, touched off a succession crisis that was settled when his daughter, Ermesinde, married Count Theobald I of Bar and solidifed her status as Countess of Luxembourg.

Ermesinde was just 11 when her father died, but her marriage ensured her rule. She was Countess for 50 years, during which time her first husband died and she married again, to Waieran, whom she then outlived. When Ermesinde died, in 1247, her son took over as Henry V (known as the Blond). The ruling house became the House of Luxembourg-Limburg. Henry succeeded in handing off his crown to a series of descendants: Henry VI, Henry VII (the first Holy Roman Emperor from Luxembourg), then a John (the Blind) and a Charles. This was the Charles IV who was also King of the Romans and Holy Roman Emperor. The last Count of Luxembourg was John the Blind's son, Wenceslaus, who restyled himself as the first Duke of Luxembourg in 1354.

Succeeding him was Charles IV's son, also named Wenceslaus, who was also King of Germany and whose reign was known for its turbulence, particularly in the religious realm. He presided over the end of the Great Schism, a dispute between Catholic Church leaders that, for a time, resulted in two lines of popes, one in Rome and the other in Avignon. Wenceslaus handed off rule of Luxembourg to his cousin Jobst in 1388, and that duke ruled for two dozen more years, giving way in 1411 to the first Duchess of Luxembourg, Elisabeth, whose grandfather was Charles IV.

Elisabeth married Anthony, Duke of Brabant, in 1409, and the pair ruled Luxembourg together until he died, in 1415. Her next co-ruler was her second husband, John III, Duke of Bavaria, whom she married in 1418; he died in 1425. Elisabeth and Anthony had had a child, who died while young, and she and John III had had no children; so when Elisabeth was contemplating succession near the end of her life, she had no heir apparent. She had incurred significant debts and so, in order to pay those off, gave the title of Duke of Luxembourg to Philip III, Duke of Burgundy, in 1441. However, when she died, a number of people contested the rule of Luxembourg. After a rather eventful nearly three decades, Philip III's son, Charles became Duke of Luxembourg, making the land subservient to his main realm, the Duchy of Burgundy.

The rule of Luxembourg then passed through the hands of Philip the Good, Charles the Bold, and Mary the Rich before ending up in the hands of her husband, Maximilian I, who founded the House of Habsburg.

The Holy Roman Emperor Charles V abdicated his thrones in 1556 and gave control of the Low Countries (of which Luxembourg was a part) to the Spanish king Philip II, who in turn gave them over to his daughter Isabella, who married Albert VII, Archduke of Austria. The tangled web of European politics wove another time, and the ruler in 1621 was Spain's Philip IV. By this time, some of the Low Countries had risen up against Spanish rule, beginning the Eighty Years War. That war, along with the wider ranging Thirty Years War, ended near the middle of the 17th Century and peace reigned for a time.

Louis XIV, France's famously ambitious and autocratic "Sun King," however, found reason to invade Luxembourg in 1684. This action provoked a strong reaction, notably the formation of the League of Augsburg; the resulting conflict, the War of the Grand Alliance, featured many of Europe's great powers and ended with a French defeat and, in 1697, the surrender of Luxembourg back to the Holy Roman Empire.

The Duchy of Luxembourg was one of a number of lands fought over in the War of Spanish Succession. During that war, Maximilian II Emanuel, Elector of Bavaria, took brief control; the treaty that ended the war restored Luxembourg to the Habsburgs. Subsequent leaders of the Holy Roman Empire who were nominally sovereign over Luxembourg included Maria Theresa, Joseph II, Leopold II, and Francis II.

After the launch of the French Revolution, French armies conquered and annexed Luxembourg, making it part of the the département of the Forçts in 1797. A brief rebellion the following year, termed the Peasants' War, was unsuccessful.

The complicated end to the Napoleonic Wars resulted in some Luxembourg lands passing under Prussian hegemony in 1813. The Congress of Vienna, two years later, formalized an independent Luxembourg. The newly autonomous entity promptly joined the German Confederation, following that action a few decades later by also joining the Zollverein, the German Customs Union.

By that time, Luxembourg was part of the Southern Netherlands and then, under William I, of the United Kingdom of the Netherlands. William increased Luxembourg's prestige by making it a grand duchy. That honor notwithstanding, many in Luxembourg sympathized with the rest of their southern neighbors during the Belgian Revolution. The 1839 Treaty of London, by which William finally admitted Belgian independence, also joined Luxembourg in a personal union with the Netherlands.

The titanic struggle between Austria and Prussia, settled emphatically in Prussia's favor during a six-week war in 1866, resulted in yet another struggle over foreign rule of Luxembourg. The 1867 Treaty of London guaranteed the grand duchy's independence and recognized its neutrality. In 1890, after the death of King William III of the Netherlands, the Luxembourg crown passed to Adolphe, head of the House of Nassau-Weilburg (while the Dutch crown went to William's daughter, Wilhelmina).