ROTTENBURG, FRANCIS (Franz) DE, Baron de ROTTENBURG, army officer and colonial administrator; b. 4 or 8 Nov. 1757 in Gdańsk, Poland, son of Franz Gottfried Rottenburg, a prominent merchant and landowner of that city, and Anne-Marie Brunatti; m. 4 Jan. 1802 Juliana Wilhelmina Carolina von Orelli, daughter of Johann Ulrich von Orelli, a Neapolitan general, in Pressburg (Bratislava, Czechoslovakia), and they had one son, George Frederick, and one daughter; d. 24 April 1832 in Portsmouth, England.

It is very likely that Francis de Rottenburg received a good education in view of his background and his later career as a military writer, but how he spent his early years is not known. He entered military service fairly late, being commissioned a second lieutenant in the Régiment de La Marck of the French army on 1 March 1782. Promoted lieutenant in 1785, he resigned in September 1791, probably because of developments in the French revolution, and returned to Poland. There he commanded a battalion of infantry in Tadeusz Kościuszko’s unsuccessful uprising against foreign rule, and was wounded at the battle of Praga in 1794.

On 25 Dec. 1795 Rottenburg joined the British army as a major in Hompesch’s Hussars, a foreign-manned unit then being raised. The next year he was promoted lieutenant-colonel and helped to raise Hompesch’s Light Infantry. When that regiment was absorbed into the 60th Foot in the spring of 1798 Rottenburg became a lieutenant-colonel in the 5th battalion, the first in the British army to be armed entirely with rifles and trained for skirmishing. He commanded the battalion during the Irish rebellion and was present at the taking of Surinam in August 1799.

About this time Rottenburg compiled a series of instructions on the training of light troops. Originally written in German, the instructions were translated into English and published by the War Office in 1798 as Regulations for the exercise of riflemen and light infantry. A number of other editions followed, and the book was used by Sir John Moore in training his Light Division. Rottenburg’s effect on military thinking suggests that he was an officer of higher than average acuity with a concern for thorough training uncommon among British officers. Moreover, he appears to have been a popular commanding officer who kept his men well controlled. In 1805 he was promoted colonel, and in 1808 he became commander of a brigade of light infantry stationed in Kent, England. The next year he commanded the light troops in the expedition under Lord Chatham to Walcheren, Netherlands.

Rottenburg had been appointed a brigadier-general on the North American staff as early as April 1808, but he did not arrive at Quebec until the late summer of 1810, by which time he had been promoted major-general. In July 1812, just after the outbreak of war with the United States, he was placed in command of the Montreal district. The responsibility was a heavy one, for Montreal was second only to Quebec in importance to the defence of the Canadas, and it was dangerously close to the American border. In 1813 Rottenburg’s duties increased when he assumed command of the administration and the troops in Lower Canada on two separate but brief occasions during the absence of Governor Sir George Prevost*. On 19 June Rottenburg replaced Major-General Sir Roger Hale Sheaffe* as administrator and commander of the forces in Upper Canada, and he held these positions until the arrival of Lieutenant-General Gordon Drummond* in December.

The increasing strains of war severely tested Rottenburg in both his civil and his military roles while he was in Upper Canada, and it cannot be said that he was conspicuously successful in either. On 28 June he forbad the distilling of rye in order to save food, an indication of the seriousness of the supply situation. Generally, however, he showed little interest and no initiative in civil matters – Chief Justice William Dummer Powell later commented that he avoided “all civil duties as much as possible” – and left a large measure of decision making in the hands of the Executive Council.

In Upper Canada, Rottenburg’s military decisions consistently demonstrated his tendency to caution and careful thought before action. During the summer of 1813, Major-General Henry Procter, commanding on the Detroit frontier, proposed an attack on the American naval base on Lake Erie at Presque Isle (Erie), Pa. However, Rottenburg discouraged the idea and refused to provide the forces necessary to carry it out. On the Niagara frontier, Rottenburg ordered raids against American outposts and confined the enemy as much as possible to the vicinity of Fort George (Niagara-on-the-Lake), where the Americans had retreated following their defeat at the battle of Stoney Creek early in June [see Sir John Harvey*]. Prevost, Rottenburg, and Major-General John Vincent* were all present with the forces in front of Fort George in August, but the war in the peninsula had reached a virtual stalemate.

The defeat of Robert Heriot Barclay* in the naval battle of Lake Erie in September was a set-back to British plans, but Rottenburg did not see any need for Procter to retreat precipitately from his position at Amherstburg. Early in October Rottenburg learned that an American attack was planned on Kingston, and he moved his headquarters there, leaving Vincent in command on the Niagara peninsula. On the 9th Vincent learned of Procter’s defeat in the battle of Moraviantown, and he retreated to Burlington Heights (Hamilton) lest he be cut off by American forces from the west. Rottenburg expected and indeed ordered Vincent to retire on York (Toronto) and then Kingston, but by 1 November he had changed his mind. Possibly influenced by Vincent, Procter, and others, he decided to retain the position at Burlington Heights with an eye to reoccupying the Niagara peninsula. Rottenburg was still at Kingston when an American army under Major-General James Wilkinson moved down the St Lawrence towards Montreal. He implemented Prevost’s instructions by sending Lieutenant-Colonel Joseph Wanton Morrison In pursuit, and Morrison was able to defeat part of the enemy command at Crysler’s Farm on 11 November.

Then followed the most controversial act of Rottenburg’s career in Upper Canada, the imposition of martial law in the Eastern and Johnstown districts to force farmers to sell supplies to the army. Although he was criticized both by individuals and by the House of Assembly, his action was probably justified, since he was not an officer who gave way to unreasonable fears. Drummond repealed the proclamation in January 1814, but three months later was compelled to impose it on the entire colony for the same reasons.

The arrival of Drummond and Major-General Phineas Riall*, both younger and experienced staff officers, allowed Rottenburg and Vincent to be withdrawn from Upper Canada. The possibility of using Rottenburg in Germany was discussed, but he was retained in the Canadas, partly because Vincent went home in ill health and partly because Prevost regarded him as a reliable subordinate. In Lower Canada, Rottenburg commanded forces on the south side of the St Lawrence at Montreal. In September 1814, when Prevost invaded the United States, he put Rottenburg in command of three brigades, thus making him in effect second in command. However, Rottenburg played no conspicuous role in the battle at Plattsburgh, and perhaps for this reason in part he escaped the barrage of criticism that descended on Prevost for the failure of the expedition. From 7 October to 3 November he again acted as administrator and commander of the forces in Lower Canada during Prevost’s absence. In December, Rottenburg was among several staff officers recalled to Britain because they were no longer needed in the Canadas, and he left Quebec in July 1815. Before his departure he served as president of Procter’s court martial. He apparently resided in England until his death, and accumulated various rewards: knight commander of the Royal Hanoverian Order in 1817, knight bachelor on 12 Feb. 1818, and lieutenant-general on 12 Aug. 1819.

Rottenburg was a competent and knowledgeable officer who demonstrated cautious and unimaginative leadership, and his outstanding qualities in the Canadas were perhaps reliability and imperturbability. Prevost recognized these assets by sending him to Upper Canada at a difficult and dangerous period in the war, and by giving him a command during the Plattsburgh campaign of 1814.

W. B. Turner