Yes, I have a number of relatives involved. And they fought on both sides. (and one may also have been at Yorktown - although as a private, not anything like an aide-de-camp)
I’ve had members of my family emigrate to America at various different times. This ranges from older cousins of my mum who emigrated as war brides in the 1940s, to people who converted to being Mormons and set out from Britain to Utah in the 1850s (you won’t believe the number of DNA matches that I have who live in Utah), to – more relevantly here – a couple of people who went over to become tobacco farmers in the 1600s.
One of them, the brother of my 8 times great grandfather (born 1636 in Gloucestershire) died in Maryland in 1673. He arrived in Maryland with one cow and an indentured servant and was granted 100 acres of land. He married and set up as a tanner, farmer and tobacco grower.
By the time of his death he owned just over 500 acres of land.
His will included:
‘I do give and bequeath unto my brother John five thousand pounds of tobacco to be shipd home for Bristoll and consigned to him he paying the freight thereof the said tobacco to be sent the next shipping after my Decease.’
He also left 10,000 pounds of tobacco to other siblings back home in England. For context, 10,000 pounds is about four and a half tons. In total, his estate had about 84,000 pounds of tobacco (about 38 tons).
He also freed his indentured servant:
‘It is my will that my servant John Merriken shall be free after the cropp is housed'.
Later, the son of his cousin also moved to Maryland in the 1690s and served an indenture there. He also owned several hundred acres of land by the time of his death.
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So, that’s the back story to how I have family in America back then.
To be totally frank, this isn’t a branch of my tree that I have studied in any sort of detail, but I have come across a few relatives who were recorded as fighting in the War of Independence.
For example, one was shown as a sergeant on the payroll of the Delaware Regiment:
‘Pay Roll of Capt Cord Hazzards Company belonging to the Delaware Regiment of foot Commanded by Col David Hall for the Month of July 1777’
A sergeant was paid 8 Dollars a month. It also gave the conversion to pounds and that was £3 per month. In comparison, a private was paid 6 2/3 Dollars or £2 10 shillings per month.
The regiment took part in many of the major battles of the war, including the battle of Brandywine Creek (Pennsylvania) on 11 September 1777. More troops fought at Brandywine than any other battle of the war. It was also the longest single-day battle of the war, with continuous fighting for 11 hours.
The British army won that battle and two weeks later captured the city of Philadelphia.
Many of the soldiers who fought with this regiment were killed in the various battles of the war, but my relative survived and went on to marry in Maryland in 1793.
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Of course, not everybody in America at this time supported independence, and there were men who fought alongside the British army. I have one relative who was recorded as a private on the payroll of ‘Colonel Samuel Bryan’s Regiment, North Carolina Militia’.
This regiment, which was a sort of local militia who did not have uniforms etc provided for them, mostly served in South Carolina. Relevant to your bit about the aide-de-camp, they took part in the battle of Camden (16 Aug 1780 in South Carolina).
The British forces at the battle of Camden were commanded by Cornwallis. So I presume that his aide-de-camp was also there.
The British decimated the American forces. The Americans had 900 killed/wounded and 1,000 captured out of a total force of about 3,700 soldiers.
Interestingly, my other relative (the one in the Delaware Regiment) was part of the American army at Camden fighting the British.
So there were distant cousins fighting on both sides of that battle.
(The Delaware Regiment had a bad time of it. All of the officers above Captain were either killed or captured and they lost 20% of the men killed. Fortunately, my relative was one of the survivors.)
After this, some parts of the North Carolina Militia did accompany Cornwallis to Virginia and surrendered at Yorktown. I don't know if my relative was in one of the companies that went to Yorktown of if he stayed in South Carolina.
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So that's what they did in the war, they had very different loyalties. However, one thing that they both had in common was enslaved people. In the 1790 census they were both recorded as having slaves, one had five slaves and the other four.
Although, by later censuses the one who fought in the Delaware Regiment didn’t (although other relations of his living nearby certainly did).
Sorry for the long ramble, but writing this out has made me realise how little I know about that side of the family and perhaps it would be worth spending more time on. I’ve just found it harder to track US records compared to UK records.