The king and his army marched north, and were joined by Alexander and Simon Frazer, with their followers.  They marched to Inverness, which, with various other castles in the north, they captured.  All of these castles were, when taken, destroyed, as Bruce had determined to leave no strongholds in the land for the occupation of his enemies.  He himself could not spare men to hold them, and their capture was useless if upon his retirement they could again be occupied by the enemy.  Returning southward they were encountered by an army under Buchan, composed of his own retainers and a party of English.  This force was completely defeated.

To the consternation of his followers Bruce was now attacked by a wasting illness, which so enfeebled him that he was unable to sit on his horse; it was the result of the many privations and hardships which he had undergone since the fight at Methven.  His brother, Lennox, the Frazers, and Archie Forbes held a council and agreed that rest for some time was absolutely necessary for the king, and that sea air might be beneficial to him.  They therefore resolved to move eastward to the Castle of Slaines, on the sea coast near Peterhead.  That such a step was attended by great peril they well knew, for the Comyns would gather the whole strength of the Highlands, with accessions from the English garrisons, and besiege them there.  The king’s health, however, was a paramount consideration; were he to die, the blow might be fatal to Scotland, accordingly the little force marched eastward.  They reached Slaines without interruption, and as they expected the castle was soon surrounded and besieged by the forces of Buchan, who had been joined by Sir John Mowbray and Sir David de Brechin, nephew of the King of England.  For some time the siege went on, but the assailants gained but little advantage, and indeed trusted rather to famine than force to reduce the castle.

Weeks passed on, and although his followers thought that he was somewhat better, the king’s health improved but slowly.  Provisions now began to run very short.  When they had come nearly to an end the Scots determined to sally out and cut their way through the vastly superior strength of the enemy.  The king was placed in a litter, his mounted knights and followers surrounded him, and round these the footmen formed a close clump of pikes; the hundred men from Aberfilly formed the front rank, as these could be best relied upon to withstand the charge of the English horse.  The gates were thrown open, and in close ranks the garrison sallied out, forming, as soon as they passed through, in the order arranged.  So close and serried was the hedge of spears, so quiet and determined the attitude of the men, that, numerous as they were, the men of Buchan and the English lords shrank from an encounter with such adversaries, and with the banner of the king and his knights flying in their centre the little band marched on through the lines of the besiegers without the latter striking a blow to hinder their way.