Scotland was an independent State until the Act of Union in 1707, after that the separate states of England, Wales, Ireland became "The United Kingdom of Great Britain".
Therefore after that, the inhabitants of Great Britain were 'British' as well as Scots or English, etc. As the combined Parliament was in London and was originally just 'English', It usually referred to the Union as 'England' and the subjects as English out of habit. especially after Culloden saw the end of the Jacobite rebellion referred to earlier.
This has lessened over time, with the secession of Ireland, the UK retained the northern Ulster County as 'Northern Ireland. Old tour Guides of 'England' usually included the other nations of the Union.
The states other than England now have their own assemblies with devolved powers from the central Parliament, tho England does not have it's own. Yet.
Anyway for matters pertaining to the whole, citizens are still occasionally referred to as English (or British). The Union uses English as the Official language, the individual states have their own languages, Wales uses it's officially on it's signage as well as English.
'English' swords can mean swords of the whole union, or just from England without rhyme nor reason. Scottish swords would more naturally pertain to Scottish pattern weapons which can be made anywhere in the UK.
Confusing isn't it?
p.s.- For tourists from outside the UK, Don't call a Scot 'English or he'll give you a good thrashing, or buy you a beer and spend an hour telling you in a barely intelligible dialect he will insist is english, why he is NOT English (Sassenach). Buy that one a beer in return before leaving. Less likely in Wales, they'll probably correct you tho, they're Welsh. English that buy summer homes in Wales have been known to have their houses torched, thankfully that tend to happen when they are not in residence. I am only a few miles from Wales, I do not, as yet, need a passport or visa to go there.
NI - some will not mind, some may correct you that they are British, some may thrash you. Some may do worse.
The UK armed forces however will more than likely band together in good natured bar fights (or real ones) against the forces of nations outside the UK and thrash them. US Yanks and Canadian or Commonwealth forces may be adopted as 'English' allies against non-English speaking nations. All in fun of course...
MINI? Made In Northern Ireland?
(just joking)