Hailes was writing in ignorance of the war which had been raised by the party of de Brus, of which James had been an active member, as his presence at Turnberry and his assent to the league had proved. The intention of this provision seems to have been generally to prevent any one of the Guardians using his official power to further schemes contrary to the interests of the Prince of England, as consort of the Queen of Scotland.
Still, nothing was expressed in this treaty about the betrothal of the Prince and the Queen. Edward, however, had already sent an embassy to Pope Nicholas IV., craving the necessary dispensation. This was granted on November 16th, and the news was allowed to leak out that it had been obtained. As soon as it reached Scotland, the four Guardians, forty-four ecclesiastics, twelve earls (including the Earl of Carrick), and forty-seven barons, signed a letter to King Edward, expressing a hope that the rumour was true, and offering their hearty consent to the alliance. On March 17th they addressed a letter to King Eric, praying him to send his daughter to be married to Prince Edward of England. A month later King Edward wrote to King Eric, informing him that he had obtained the Papal dispensation, and requesting him to send Queen Margaret to him in England. On July 18, 1290, a memorable treaty was concluded at Birgham on the Tweed, defining the relations between England and Scotland in the event of the marriage taking place.
It was agreed, among other things, between the English and Scottish commissioners: