Hiram Maxim was American Born but was a British subject when he invented the Maxim Gun which was developed by a British financed company (Vickers) and first used by the British Army.
Not exactly a large American component there...
The British should claim reparations from the Danes (Vikings) for the rape and pillage and extortion of Dane Geld (with interest), also from the Italians for the Roman invasion in 55BC and from the French (Normans) for the invasion in 1066.
Other than the fact he was born here and didn't emigrate to the UK until he was well into his fourties anyway.
Whatever. The Brits can have Mr. Maxim. We had John Moses Browning.