After years of fighting, Bruce realised that he would have to secure Scotland’s independence through diplomacy.
First he had to get support from the Church. Scotland had remained isolated from the Roman Catholic Church due to Bruce's excommunication.
In 1320, the nobles of Scotland sent a letter to Pope John XXII to argue for Scotland’s freedom from the English. The letter became known as the 'Declaration of Arbroath' and was important for a number of reasons:
In fact, there had been three letters sent to the Pope, each attempting to persuade him to recognise Scotland as an independent country.
One was from Bruce himself, one was from the clergy of Scotland and one was from the nobles. However, the letter from the nobles is the only one to have survived to this day.
This was a very unstable time for England.
Edward II was a weak king. In 1327 he was deposed by his wife, Isabella of France, and her lover, the English noble, Roger Mortimer.
Edward III was crowned as the new king of England. A newly-crowned king is always at risk of being overthrown. Edward III was in particular danger as he was only a young boy, unable to take full charge himself.
Bruce sent an invasion force to England. As a result of this pressure from Bruce, as well as the threat from rebellious English nobles, Isabella and Mortimer had to request a truce.
In 1328, the two sides signed the Treaty of Edinburgh-Northampton in which:
Bruce himself was growing old and had long been suffering from an undiagnosed disease, probably leprosy. The following year, 1329, Robert Bruce died leaving Scotland relatively secure and independent.