[Jim McDougall]

While I am by no means any sort of expert, I have been interested in swords of these types since the 1960s, and have a 'working' knowledge of the basics. The real experts are those who specialize in certain fields, and here Bryce and Radboud and several others come to mind. Still, Ive never been shy about speculating, and always learn from the corrections that often ensue.

Having said that, my feel, mostly from looking through "Swords and Blades of the American Revolution" (George Nuemann, 1973), there many hangers/short sabers etc. with these kinds of pronounced single back fullers, most are with slight curve and varying lengths. These are typically 1750s-70s and of course fall into British, French and German categories, naturally many listed as American. Keep in mind that Americans in those times were 'colonists' and essentially British. British materials including arms were imported into America through the 18th century and still coming in through the War of 1812.

With the focus primarily on the blade, it seems that British blade makers, who were few, were Samuel Harvey, Nathaniel Jeffries and a Dawes., with Gill, Wooley and Osborn coming in later by 1770s. It is unclear whether these men were cutlers or actually producing blades, and the practice of 'salting' stock and finishing of raw blades was well known from the times of Hounslow and Shotley in the 17th c.

It seems that by 1784, Gill MUST have been producing blades as he pronounced that British blades (focused on his) were superior to the German imports that were prolific. This would suggest of course that Harvey, Wooley and Osborn were as well.
I would point out here that it seems that Harvey had an unclear connection with the Oleys of Shotley Bridge to the north, who seems to have been supplying blades as well.

The reason for bringing up the conundrum of British blade production in these times is looking at the character of the blade on the sword discussed.
If this indeed has a crowned letter, if a G or TG it of course suggests Thomas Gill and his period of work. The crowned initials, or in cases numbers (suggesting inspectors) were a notably British convention then, but there were inconsistencies.

The provenance to New York while helpful, does not actually lend to determining the classification or analysis of the sword, It may have ended up there in many circumstances.

The hilt type is of 18th century European cavalry saber style which as noted did arrive in England for the 1780-88 'patterns', but does not correspond enough to either to be placed among these forms.

The hilt seems to have the quillon 'bent in', and frankly might be from European context, perhaps even Dutch, where many swords were always coming into America. The idea of the blade being British and from mid to late 17th c. is my primary motivator.

Basically, the blade seems pretty set, the hilt added is the issue, and regardless of outcome, I think it falls into c. 1800 context. Stirrup hilts had become so ubiquitous in many nations, then factor in the militia and other sectors it becomes a true challenge. I feel that it is British, but hard to say more defined.

The reason I added the four unofficial (post #6) 'patterns' of British hilts of 1770-1790s was to give context.