Born in Copenhagen in 1716, Johann Georg Ziesenis was a pupil of his father Johan Jürgen Ziesenis. He became a German citizen in 1743 and was first appointed court painter in Zweibrücken, then in Mannheim. In 1760 he entered into the service of George II of Hannover and, subsequently, George III; Ziesenis also worked in Berlin and Brunswick. The Royal Collection owns a significant amount of Ziesenis portraits, illustrating members of various eighteenth-century noble German dynasties – notably from the houses of Mecklenburg-Streliz and Brunswick-Wolfenbüttel.

Producing around 260 works in his lifetime, most of which were portraits, Ziesenis is remembered for his intimate portrayals of the future wife of George III, Charlotte of Mecklenburg-Streliz, Crown Prince Frederick and Frederick II. He began his career working in a traditional baroque style but, inspired by Rubens and Van Dyck, effected a transformation in the 1750s, introducing a heightened psychology to his character studies. Ziesenis practised a new type of enlightened portraiture, the private court portrait. He depicted his subjects at ease in natural surroundings, an emphasis on education and worldliness rather than on power. In this way Ziesenis' work ranks alongside the great English eighteenth-century portraitists. Indeed, his biographer, F. F. Kuntze, states that in invention and execution Ziesenis was the highpoint of eighteenth-century German portraiture and his best work ranks alongside the great painters of the English enlightenment.

In the later part of his career, Ziesenis' art exemplified the period of Zopfstil or Citizen's Rococo, literally a "pig-tail style" coined after Louis XVI and the waning Ancien Regime. This new style stood at a transition point between late Rococo and the burgeoning reprisal of stark, Hellenic Classicism in the hands of Winckelmann, best displayed in the furniture of the time. Ziesenis' portraits of this period introduce a certain air of civic responsibility and mark a departure from the florid pleasure gardens of Rococo fashion.

Duke Ferdinand of Brunswick-Wolfenbüttel was a talented Prussian Field Marshal known for his participation in the War of Austrian succession, the Second Silesian War and the Seven Years' War. From 1757 to 1762 he led a victorious Anglo-German offensive against French attempts to occupy Hanover, serving alongside his nephew, Karl II, Duke of Brunswick-Wolfenbüttel (1735-1806), and the Duke of Cumberland. This naturally earned the gratitude of the Hanoverian monarchs, with the result that the Royal Collection has three pairs of portraits depicting this heroic uncle and nephew team: this pair (RCIN 405906-7), another of similar compositions (RCIN 401370 & 401379) and another by Johann Heinrich Tischbein (RCIN 404638 and 404640). Ferdinand here wears a blue frock coat, the riband and star of the Garter and the cross of Baver-Brandenburg. A number of other versions of this portrait exist - in the Brunswick Landesmuseum, the Duke of Portland's collection, a German private collection, the Deutsches Historisches Museum in Berlin and the Herzog Anton Ulrich Museum in Brunswick