take command of a cavalry brigade (consisting of the 7th, 10th, and 18th light dragoons) under Lord Uxbridge in the Duke of Wellington's army assembling in Belgium. He arrived on 3 May at Ninove, where his brigade was assembled. Towards the end of May the 7th hussars were transferred from Vivian's to Sir C. Grant's brigade and replaced by the 12th hussars of the king's German legion. On 13 June Vivian, having personally ascertained that the French were concentrating, reported it to headquarters. On the 15th he was present at the Duchess of Richmond's ball at Brussels, which he left to march on Enghien and thence to Quatre Bras, where he arrived after a forty-mile march over bad roads just too late to assist in defeating the French attack. On the 17th Vivian's brigade assisted to cover on the left the British retreat to Waterloo, encountering a tremendous storm of rain, which, however, relieved them of some pressure from the enemy. Having bivouacked in the vicinity of the forest of Soignies on the night of the 17th, his brigade was drawn up on the morning of the 18th in rear of the Wavre road. It suffered little until towards the close of the last attack, as the ground on the left did not admit of the cavalry advancing.
About six o'clock in the evening, ascertaining that the cavalry in the centre had suffered severely, Vivian took upon himself to move his brigade from the left to the right centre of the British line, arriving most opportunely as Bonaparte was making his last and most desperate efforts. Wheeling his brigade into line close in rear of the infantry, Vivian was ready to charge directly they had retreated through his intervals. Lord Edward Somerset, with the remnant of the two heavy cavalry brigades (some two hundred out of two thousand), retired through Vivian's brigade, which was then for about half an hour exposed to a hot fire of shot, shell, and musketry. The presence, however, of Vivian's brigade, which was shortly after followed by the brigade of Sir John Ormsby Vandeleur [q. v.], inspired the infantry with fresh confidence. On the repulse of Bonaparte's two huge columns of attack by the fire of the allies, Vivian led his brigade to attack the French reserves posted close to La Belle Alliance. Charging with the 10th light dragoons (the 18th being in support and the king's German legion in reserve), as soon as the 10th were well mixed up with the enemy and the French making off, he galloped to the 18th. En route he was attacked by a cuirassier, but, giving him a thrust in the neck with his left hand (his right hand was in a sling from his Peninsula wound), his little German orderly cut the fellow off his horse. With the 18th light dragoons he charged the second body of cuirassiers and chasseurs, not only defeating them, but taking fourteen guns which had been firing at them during the movement. He then directed the 10th to charge an infantry square, which was gallantly carried out, the French cut down in their ranks, and Count Lobau, who commanded an army corps, taken prisoner. The last shot having been fired, the pursuit lasted as long as it was possible to see, and Vivian bivouacked for the night at Hilaincourt.
On 19 June Vivian moved near Wellington's headquarters, and his brigade formed the advanced guard in the march to Paris. On the 26th, near Nesles, a reconnoitring party of the 10th hussars captured General Lauriston, aide-de-camp to Napoleon. On 2 July Vivian reached Bourget. On the 8th he went into Paris to see the king enter, and on the 10th proceeded on leave of absence to England. For his services at Waterloo Vivian, who was mentioned in despatches, received the thanks of both houses of parliament, knighthood of the royal Hanoverian order, of the Austrian order of Maria Theresa, and of the Russian order of St. Vladimir. During the occupation of France he was with his brigade in Picardy. He returned to England with the army in 1818, and was for a short time unemployed. On the disbandment of the 18th hussars on 10 Sept. 1821, the soldiers of the regiment presented him with a silver trumpet and banner purchased with part of the prize-money due to them for horses of the enemy captured by the brigade at Waterloo. This trumpet was presented by the second Lord Vivian to the new regiment of 18th hussars on 10 Sept. 1880.
In 1819 Vivian was sent to Newcastle-on-Tyne on account of disturbances which had occurred there, and thence to Glasgow, where serious riots were apprehended. In 1820 he was elected a member of parliament for Truro, and continued to represent it until 1825. From 1825 until 20 July 1830 he held the appointment of inspector-general of cavalry. On 22 June 1827 he was promoted to be lieutenant-general, and on the following day received the colonelcy of the 12th or Prince of Wales's royal lancers. From 1826 until 1831 he represented Windsor in parliament. During the time Vivian sat in the House of Commons he was a frequent speaker, especially on military subjects. In 1828 he was created a baronet. On 1 July 1831 he was appointed commander
