1810 ca. Full Dress Jacket, Lothian Yeomanry Cavalry, Britain. The East Lothian Yeomanry Cavalry was raised as a one troop formation at Haddington in May 1797. Five years later a second troop was raised and in 1803 a third and fourth troop. The regiment was reduced to one troop in 1823 and disbanded 15 years later. National Army Museum, London, UK.   https://books2read.com/SuziLoveFashionMen1800-1819 In Jane Austen’s time, or the early 1800s, gentlemen were seen in military coats like this often because many Englishmen were involved in the long lasting wars against Napoleon. .