During the Waterloo Campaign, the 12th Light Dragoons were attached to Sir John Ormsby Vandeleur's light cavalry brigade. At the Battle of Waterloo, the 12th and 16th Light Dragoons were told to charge down the slope, but no further, to support the withdrawal of the Union Brigade of heavy cavalry. But, like the Union Brigade, the light horse charged too far. Ponsonby was wounded in both arms, and knocked off his horse by another sabre cut. A French lancer saw him move where he lay and stabbed him in the back with his lance, exclaiming "Tu n'es pas mort, coquin". A French skirmisher then robbed him but luckily for Ponsonby, a Major de Laussat of the French Imperial Guard Dragoons found him and treated him kindly, giving him some brandy and promising to send help should the French prove victorious. Later, another French skirmisher used Ponsonby as a shield as he talked with him and fired over his body. Toward the end of the battle, he was ridden over by Prussian cavalry. During the night after the battle, he was roughed up by a Prussian looking for plunder, and a mortally wounded soldier of the Royal Dragoons had crawled upon Ponsonby's legs and lay dying. At last, Ponsonby was discovered by a soldier of the 40th Foot, who stood guard over him during the night. The next morning he was carried away in a cart, to a surgeon who tended to his seven major wounds. Despite his wounds, he was bled of over two days but nevertheless survived. He convalesced under the supervision of his sister Lady Caroline Lamb who nursed him back to health.
Later career
Ponsonby went on half-pay on 26 August 1820, and was appointed "inspecting field officer" in the Ionian Islands on 20 January 1824. On 27 May 1825, he was promoted major-general, commanding the troops in the Ionian Islands. The next year, on 22 December 1826, he was appointed Governor of Malta, and remained there for eight and a half years. He met Baron de Laussat, his saviour at Waterloo, in 1827. During his Maltese tenure, he was made GCMG in 1828, and KCB and KCH in 1831. He left the governorship in May 1835, and was appointed colonel of the 86th Regiment of Foot on 4 December 1835. He was transferred to the colonelcy of the Royal Dragoons on 31 March 1836. During this period, he maintained a high degree of interest in the handling of cavalry, and corresponded with Wellington. He died suddenly at an inn near Basingstoke on 11January 1837 and was buried in the crypt of St Nicholas' Church, Hatherop, Gloucestershire. In 1838, Ponsonby's Column was erected in Valletta in honour of the governor. It was destroyed by lightning in 1864.
Family
On 16 March 1825, Ponsonby married Lady Emily Charlotte, the youngest daughter of Henry Bathurst, 3rd Earl Bathurst. They had three sons and three daughters:
