Braunschweig is the historic seat of the House of Guelph in Northern Germany. It was here, close to the seat of the Hanoverians, that the Guelph dynasty started their rise to power. First mentioned in a document in 1031, Braunschweig rose to become the Guelph dynasty's capital in the twelfth century, as Henry the Lion expanded the town of Braunschweig into a city. Throughout the centuries, the House of Guelph shaped the city's history, and – with one interruption – the Guelph Dukes had their residences there until the 20th century. The Guelphs were the most influential noble family in all of Northern Germany. They patronised numerous innovations in commerce, culture and the sciences, thus helping Braunschweig and the surrounding lands to prosper.

Today, many sights in the city of Braunschweig recall the Guelph dynasty's history as well as its close ties to the English crown. Among the most famous sights are the Castle Square with Dankwarderode Castle and St. Blasii Cathedral, Richmond Palace with its adjoining landscaped gardens as well as the reconstructed Ducal Palace.

The mediaeval seat of the Guelph dynasty in the city centre was Dankwarderode Castle built by Henry the Lion, the family's most famous and powerful son. In 1168, Henry the Lion married the English royal princess Matilda, sister of Richard the Lionheart. Their son Otto IV was raised at the court of Richard the Lionheart. To this day, the Castle Square exudes a sense of ancient imperial grandeur. Freely reconstructed since 1887, the castle takes us back to a time 850 years ago, when it was designed in the style of imperial palaces of the time. Henry the Lion's physical legacy also includes the lion statue – a symbol of his reign and the first free-standing monument north of the Alps since Antiquity (the original lion resides inside the castle as part of the Herzog Anton Ulrich Museum's exhibition) as well as St. Blasii Cathedral, which houses the Guelph dynasty's tombs, reflecting the concern for the soul’s salvation after death. In those times Braunschweig was already one of the largest mediaeval cities. After Emperor Barbarossa overthrew the Duke in 1180, valuable donations were made to the cathedral as a sign of penitence: the Gospel of Henry the Lion (today located in the Herzog August Library in Wolfenbüttel), in 1188 the Lady Altar and the Seven-Armed Candelabra, which can still be admired inside the cathedral today. Henry's successors continued to embellish the cathedral. It came to house the tomb of Henry's most notable son, who rose to become Otto IV, the only emperor descended from the House of Guelph. Despite Henry's downfall, the Guelphs remained wealthy, and their allies, including the English king Richard the Lionheart, pushed for Otto to be elected King of the Romans in 1198. In 1209 Otto was crowned Emperor of the Holy Roman Empire, but was unable to persevere against his Staufen rivals within the empire. He failed and continued to concentrate on expanding the city of Braunschweig like his father did. Around 1235, the Gothic tomb figures of Henry and Matilda added a monument to the cathedral that was without equal in all of Germany. It was crafted by unknown masters from Magdeburg, who drew inspiration from the imposing portals of the Chartres, Reims and Bamberg cathedrals, prior to the establishment of the Duchy of Braunschweig-Lüneburg in 1235.

Located to the south of Braunschweig, Richmond Palace conveys a sense of the separation of the Braunschweig and Lüneburg lines of the House of Guelph that occurred in 1428. After this division, the important Braunschweig-Wolfenbüttel line, which died out in 1884, and the Lüneburg-Calenberg line, which later became the Hanoverian line of the Guelphs, emerged.
In 1765 Charles William Ferdinand, heir and son of the enlightened Duke Charles I., married Princess Augusta, sister of the British King George III of the house of Braunschweig-Lüneburg (or Hanover). Augusta's marriage to Charles William, arranged for purposes of alliance, was the only one between the two related houses. Otherwise, the relationship between the neighbouring principalities was characterised by rivalry.
As Augusta had experienced urbane sophistication at the royal court in London, her Braunschweig residence disappointed her. As a gesture of reconciliation and a present for the birth of the heir in 1766, her husband had Richmond Palace built for her as a secluded, private residence. The ensemble skilfully blends the palace's South German and French architectural styles employed by architect Karl Chr. W. Fleischer with an English landscape garden, created by English landscape gardener Lancelot "Capability" Brown, who also designed the gardens in Augusta's home of Richmond. Today, the park has largely been restored. This makes Braunschweig home to one of the oldest English landscape gardens on the continent.

The structural shell and facade of this youngest of the Guelph residences, originally designed in the 1830s by Carl Theodor Ottmers, was reconstructed between 2005 and 2007. This gem of late Classicist corporeal architecture rounded off the ensemble of local palaces again, drawing attention not only to the new palace itself, but also to its predecessor: the Grauer Hof, which had burned down in 1830. The large Ducal Palace had been surrounded by smaller palaces, like the aforemen-tioned maison de plaisance Richmond Palace. The reconstructed Ducal Palace lets visitors experience the last flowering and the end of the duchy. The Palace Museum, a popular part of the building predominantly used for cultural purposes, illustrates the tragic stories: the degradation of the duchy to a part of the Napoleonic Kingdom of Westphalia that existed from 1807 to 1813 and its liberation by Augusta's eminent son Frederick William, better known among the people as "the Black Duke", who died in 1815 during skirmishes preceding the decisive battle of Waterloo against Napoleon. The museum also illustrates how the early death of their parents and their first years at the liberal court in London weighed upon the ducal sons Charles and William as they grew up. Only seven years after his inauguration in Braunschweig, Charles II fell out completely with the Estates of the Realm and was forced to leave the city on 7 September 1830. William, his sensible brother, took over as Duke, had the new Ducal Palace built (which was destroyed in World War II and torn down in 1960), brought peace to the land, maintained a friendly relationship to the Hanover King, and tided the duchy over the war year of 1866, which marked the end of the House of Hanover. William's reign brought prosperity and progress – the industry and the railways flourished – and, imitating the Imperial cities of Vienna and Paris, he surrounded the central palace to the east of the new town quarters with a sheaf of buildings to house museums, educational institutions and transport facilities: University, State Theatre, Herzog Anton Ulrich Museum and the former railway station were arranged with the Palace as the focal point of orientation, a fact clearly visible from the platform supporting Europe's largest quadriga atop the Ducal Palace.