Gothic Sword questions

[RealWing]

A local museum in Ontario, Canada acquired this sword which was found in an old barn that was being torn down. I would appreciate any details on its possible origin, date or history.
It is believed to be from the 1810-1822 era We think it is called a Gothic Sword because the guard has curves on it like Gothic Architecture? It also has on it the Royal Cypher which is believed to be the monogram of the ruling monarch.

Hopefully someone can identify which monarch had that cypher. I think it
is George II but am not sure as he used an arabic 2 on his cyphers and the might be what the bottom of the cypher is below the crossed sword and baton ??

On the sword is the name Captain Robert James Stewart ------------------- no last name

Thanks

Jim