The Treaty of Northampton was the formal document that concluded the First Scottish War of Independence between Robert the Bruce and Edward II and his successor Edward III. It was negotiated in Edinburgh on the 17th March 1328 and formally signed and and ratified in Northampton on the 4th May 1328 (but formally backdated to the 1st March). It is therefore also sometimes known as the Treaty of Edinburgh (although this risks confusion with the other Treaty of Edinburgh of 1560) and sometimes by the ungainly combination title of the Treaty of Edinburgh-Northampton.
The Treaty takes the form of a proclamation by Edward III, which after an admission that the dire conflicts of wars waged have afflicted for a long time the Kingdoms of England and Scotland contains two important provisions.
Firstly it formally recognises the independence of Scotland;
that the Kingdom of Scotland ... shall belong to .. Lord Robert, by God's grace illustrious King of Scotland, and to his heirs and sucessors, separate in all things from the Kingdom of England, whole, free and undisturbed in perpetuity, without any kind of subjection, service claim or demand.
and secondly renounces any claim by England for dominion over Scotland;
we denounce and demit to the King of Scotland, his heirs and sucessors, whatsoever right we or our predecessors have put forward in any way in bygone times to the aforesaid Kingdom of Scotland
Of course, it has to be said that Edward III later displayed little regard for the terms of the treaty and as soon as Robert the Bruce was dead Edward was busy promoting the rival claims of Edward Balliol against those of Robert's infant son David. On the other hand, the Scots had similarly paid little regard for the terms of previous agreements they had signed, such as the Treaty of Abernathy for one, when they started the war in the first place, so we should not be too harsh on poor Edward.
The Treaty of Northampton
To all Christ's faithful people who shall see these letters, Edward, by the grace of God, King of England, Lord of Ireland, Duke of Acquitaine, greeting and peace everlasting in the Lord.
Whereas, we and some of our predecessors, Kings of England, have endeavoured to establish rights of rule or dominion or superiority over the realm of Scotland, whence dire conflicts of wars waged have afflicted for a long time the Kingdoms of England and Scotland: we, having regard to the slaughter, disasters, crimes, destruction of churches and evils innumerable which, in the course of such wars, have repeatedly befallen the subjects of both realms, and to the wealth with which each realm, if united by the assurance of perpetual peace, might abound to their mutual advantage, thereby rendering them more secure against the hurtful efforts of those conspiring to rebel or to attack, whether from within or without:
We will and grant by these presents, for us, our heirs and successors whatsoever, with the common advice, assent and consent of the prelates, princes, earls, barons and the commons of our realm in our Parliament, that the Kingdom of Scotland, within its own proper marches as they were held and maintained in the time of King Alexander of Scotland, last deceased, of good memory, shall belong to our dearest ally and friend, the magnificent prince, Lord Robert, by God's grace illustrious King of Scotland, and to his heirs and successors, separate in all things from the Kingdom of England, whole, free and undisturbed in perpetuity, without any kind of subjection, service claim or demand.
And by these presents we denounce and demit to the King of Scotland, his heirs and successors, whatsoever right we or our predecessors have put forward in any way in bygone times to the aforesaid Kingdom of Scotland.
And, for ourselves and our heirs and successors, we cancel wholly and utterly all obligations, conventions and compacts undertaken in whatsoever manner with our predecessors, at whatsoever times, by whatsoever Kings or inhabitants, clergy or laity, of the same Kingdom of Scotland, concerning the subjection of the realm of Scotland and its inhabitants.
And wheresoever any letters, charters, deeds or instruments may be discovered bearing upon obligations, conventions and compacts of this nature, we will that they be deemed cancelled, invalid, of no effect and void, and of no value or moment.
And for the full, peaceful and faithful observance of the foregoing, all and singular, for all time we have given full power and special command by our other letters patent to our well-beloved and faithful Henry de Percy our kinsman, and William de la Zouche of Ashby and to either of them make oath upon our soul. In testimony whereof we have caused these letters patent to be executed.
Northampton on the 1st Day of March in the Year of our Lord 1328
Endorsed by Edward III, King of England and council in Parliament.
The text of the Treaty resides at a number of locations such as,
http://www.scottish-history.net/histor_docs/shared/northampton.htm
http://www.etsu.edu/cas/history/docs/edinburgh.htm