, by . He was made a Prussian general in 1773.
War of the Bavarian Succession From 1778 to 1779 he served in the
War of the Bavarian Succession.
Frederick II praised the prince personally for his conduct during the war.
Invasion of the Netherlands In 1787 the Duke was made
Generalfeldmarschall (
field marshal) in the
Prussian army.
Frederick William II of Prussia appointed him as commander of a 20,000-strong Prussian force which was to invade the
United Provinces of the Netherlands (The Dutch Republic). The goal was to suppress the
Patriots of the
Batavian Revolution, restoring the authority of the
stadtholder William V of the
House of Orange. Much of the country was in open revolt against William, whose personal troops were unable to quell the Patriot militias and the various Dutch provinces refused to aid him. The
Encyclopædia Britannica described
the Duke's invasion: "His success was rapid, complete and almost bloodless, and in the eyes of contemporaries the campaign appeared as an example of perfect generalship". The Patriots were out-manoeuvred and overwhelmed: their militias were unable to put up any real resistance, were forced to abandon their insurrection, and many Patriots fled to France. The Duke's forces entered the Netherlands on 13 September and occupied
Nijmegen that day. The largest Patriot force, 7,000 men under the
Rhinegrave of Salm, was quickly out-manoeuvred and forced to abandon
Utrecht, which the Duke occupied on 16 September. The Prussian force captured
Gorcum on the 17th after a short artillery bombardment, followed by
Dordrecht on the 18th and
Delft on the 19th. They entered
The Hague on the 20th, from which the Patriots had been forced to withdraw following a loyalist insurrection on the 17th.
Amsterdam, the last city occupied by the Patriots, surrendered on 10 October. The campaign had taken less than a month. William V was restored to power, which he was to hold
until 1795. Both contemporaries and historians have praised the Duke's decisive campaign, in which he manoeuvred to concentrate his forces and achieve overwhelming local superiority, before moving on to the next city. He also received credit for the low number of casualties; one British observer suggested that "the sap of the trees was the only blood shed" (an exaggeration), referring to the wooden
palisades and batteries constructed by both sides.
War of the First Coalition At the outbreak of the
War of the First Coalition in the early summer of 1792, Ferdinand was poised with military forces at
Coblenz. After the
Girondins had arranged for France to declare war on Austria, voted on 20 April 1792, the Catholic
Holy Roman Emperor Leopold II and the Protestant King of Prussia
Frederick William II had combined armies and put them under Brunswick's command.
The Brunswick Proclamation , primary author of the Brunswick Manifesto The "
Brunswick Proclamation" or "Brunswick Manifesto" that he now issued from
Coblenz on 25 July 1792, threatened war and ruin to soldiers and civilians alike, should the
Republicans injure
Louis XVI and his family. His avowed aim was: to put an end to the anarchy in the interior of France, to check the attacks upon the throne and the altar, to reestablish the legal power, to restore to the king the security and the liberty of which he is now deprived and to place him in a position to exercise once more the legitimate authority which belongs to him. Additionally, the manifesto threatened the French population with instant punishment should they resist the Imperial and Prussian armies, or the reinstatement of the monarchy. In large part, the manifesto had been written by Louis XVI's cousin,
Louis Joseph de Bourbon, Prince de Condé, who was the leader of a
large corps of émigrés in the allied army. It has been asserted that the manifesto was in fact issued against the advice of Brunswick himself; the duke, a model sovereign in his own principality, sympathised with the constitutional side of the French Revolution, while as a soldier he had no confidence in the success of the enterprise. However, having let the manifesto bear his signature, he had to bear the full responsibility for its consequences. The proclamation was intended to threaten the French population into submission; it had exactly the opposite effect. In Paris, Louis XVI was generally believed to be in correspondence with the Austrians and Prussians already, and the republicans became more vocal in the early summer of 1792. Rather than assuring the continued existence of the French monarchy, Brunswick's proclamation would instead ensure its downfall; the manifesto was rapidly distributed in Paris on 28 July, apparently by monarchists, who badly misjudged the effect it would have. The Brunswick Manifesto seemed to furnish the agitators with a complete justification for the revolt that they were already planning. When news spread of a combined Austrian and Prussian army led by Brunswick marching into French soil on the days after the Manifesto was publicised, the Paris populace, already incensed by the threat against the city, exploded into violence. The first violent action was carried out on
10 August, when the
Tuileries Palace was stormed.
Invasion of France , painted by
Horace Vernet. The Duke was disappointed that the British remained neutral. His initial advance into France was slowed by poor weather, the rough terrain of the
Forest of Argonne, and an outbreak of
dysentery among his troops. The Duke was less successful against the French citizens' army that met him at
Valmy. Having secured
Longwy and
Verdun without serious resistance, he turned back after a mere skirmish in Valmy, and evacuated France. Initially the Duke intended to winter in the fortress of
Verdun, before resuming the campaign in France the following spring. However, Kellerman's forces outflanked him by advancing up the Rhine, recapturing French possessions there. The Duke abandoned Verdun on 8 October and Longwy on 22 October, before retreating back into Germany. When he counterattacked the Revolutionary French who had invaded Germany, in 1793, he recaptured
Mainz after a long
siege, but resigned in 1794 in protest at interference by
Frederick William II of Prussia.
War of the Fourth Coalition . Prussia did not take part in the
Second Coalition or the
Third Coalition against Revolutionary France. However, in 1806 Prussia declared war on France, beginning the
War of the Fourth Coalition. Despite being over 70 years old, the Duke of Brunswick returned to command the Prussian army at the personal request of
Louise, Queen of Prussia. By this stage the Prussian army was regarded as backward, using outdated tactics and with poor communication. The structure of the high command has been particularly criticised by historians, with multiple officers developing differing plans and then disagreeing on which should be followed, leading to disorganisation and indecision. The duke commanded the large Prussian army at Auerstedt during the double
Battle of Jena–Auerstedt on 14 October 1806. His forces were defeated by
Napoleon's marshal
Davout, despite the Prussians outnumbering the French around Auerstedt by two to one. During the battle he was struck by a musket ball and lost both of his eyes; his second-in-command
Friedrich Wilhelm Carl von Schmettau was also mortally wounded, causing a breakdown in the Prussian command. Severely wounded, the Duke was carried with his forces before the advancing French. He died of his wounds in
Ottensen on 10 November 1806. The duke's body was provisionally laid to rest in the Christianskirche at Ottensen in 1806. It was later transferred for reburial in
Brunswick Cathedral on 6 November 1819. ==Family==