The Right to Arms from the English Bill of Rights

That the subjects which are Protestants may have arms for their defence suitable to their conditions and as allowed by law

The Bill of Rights, 1 Will & Mary Sess 2 c 2
As you can see this right is limited to protestants
The right to arms is also "suitable to their condition"--that is arms that were suitable to the class of holder. IN other words,the rich could own pistols and swords, while the peasantry would own pikes or longbows.
Additionally, this right is as allowed by law. In other words,the right could be limited by law. In the case of the longbow, it use was relate to the military,as was also the case with the pike.
I should also add that Britain was the first society to institute Gun Control beginning with the Pistols Act 1903 and tighter controls coming under the Firearms Act of 1920.
I should also add that this relates to National Defence, not personal. the right os self-defence at common law has disliked the use of deadly force and has worked to discourage it. Blackstone points out in his commentaries (Blackstone’s Commentaries on the Laws of England, Book the Third, Chapter the First: Of the Redress of Private Wrongs by the Mere Act of Parties p.3 ):

In the English law particularly it is held an excuse for breaches of the peace, nay even for homicide itself: but care must be taken that the resistance does not exceed the bounds of mere defence and prevention; for then the defender would himself become an aggressor.

Thus excessive force can make one the aggressor. It is still common today for those who use excessive force to be prosecuted and convicted (e.g., Tony Martin and Munir Hussein).
That was how the law of self-defence was understood at the time the Constitution was adopted as well.
I am going to reiterate that the Fifth Auxiliary Right mentioned by Blackstone in his commentaries comes in his discusstion of the English Bill of Rights, whereas self-defence is addressed in another section of the commentaries (Of the Redress of Private Wrongs by the Mere Act of Parties).
DO NOT CONFUSE THE TWO
So, the right which "pre-existed" the Second Amendment was a very limited one--not the one promoted by the believers in "gun rights".
This was a well known fact at the time of the adoption of the US Constitution.

St. George Tucker wrote this regarding the English Bill of Rights in his 1803 edition of Blackstone’s Commentaries:

In England, the people have been disarmed, generally, under the specious pretext of preserving the game: a never failing lure to bring over the landed aristocracy to support any measure, under that mask, though calculated for very different purposes. True it is, their bill of rights seems at first view to counteract this policy: but the right of bearing arms is confined to protestants, and the words suitable to their condition and degree, have been interpreted to authorise the prohibition of keeping a gun or other engine for the destruction of game, to any farmer, or inferior tradesman, or other person not qualified to kill game. So that not one man in five hundred can keep a gun in his house without being subject to a penalty.