Lieutenant-General Robert Ballard Long (4 April 1771 – 2 March 1825) was an officer of the British and Hanoverian Armies who despite extensive service during the French Revolutionary and Napoleonic Wars never managed to achieve high command due to his abrasive manner with his superiors and his alleged tactical ineptitude.

With the aid of his family's substantial financial resources, Long had been promoted to captain by November 1793 and served with his regiment in Flanders during the Duke of York's unsuccessful campaign there.

[3] In the winter of 1794/95, Long had left his regiment and was attached to the staff of General Sir George Don during the retreat into Germany and return to England.

[3] At the conclusion of the rebellion, Long served with the York Hussars, another Hanoverian cavalry unit, at Weymouth until the Peace of Amiens.

He ascribed virtually all of the superiorities of organisation or training that he claimed for his regiment, over the rest of the British cavalry, to Long's initiatives when in command.

The historian Charles Oman later sided with Beresford in calling the Campo Mayor action reckless, though without naming Long.

[7] Beresford also claimed that his taking personal command of the heavy dragoons had prevented Long from ordering them to attempt a suicidal charge against French infantry squares .

In contrast to Oman's opinion, the historian Sir John Fortescue wrote, "Of the performance of Thirteenth, who did not exceed two hundred men, in defeating twice or thrice their numbers single-handed, it is difficult to speak too highly.

"[8] Long was of the opinion, and was subsequently supported in this by the historian Sir William Napier, that if Beresford had released the British brigade of heavy dragoons he would have been able to force the whole French column to surrender.

Long also served under Lumley at the Battle of Usagre on 25 May 1811, when the British cavalry neatly trapped two regiments of French dragoons at a bridge, inflicting severe casualties.

When Marshal Soult's large-scale attack across the Pyrenees was launched, on 25 July 1813, it caught Wellington's forces off guard and in an extended state.

General Lowry Cole sent a dispatch to Wellington to say that a French army of about 35,000 men had forced him from his defensive position and that he was falling back.

Long refused the proffered posting as a divisional commander in Scotland and scornfully retired to his estate at Barnes Terrace, Surrey.

If his record as a cavalry general was chequered he, nevertheless, contributed substantially to a number of victories, including Los Santos, Usagre and Arroyo dos Molinos.

To his subordinates he appears to have been a popular and respected figure; characteristically he refused to allow Wellington's censure of the 13th Light Dragoons, following Campo Mayor, to be entered in the regiment's official record.

"[6] The officers and men of the 13th Light Dragoons repaid his regard for them when they voluntarily subscribed to the purchase of a set of silver plate for Long when he was replaced in command of his brigade.

When the men he made personal enemies of included royal princes (both later to become kings) and a field marshal (albeit in the Portuguese service) Long's career and reputation were bound to be adversely affected.