Forbes was arrested on his way to join the 1745 Jacobite rising and was held in Stirling and Edinburgh Castles following his arrest. After his release from prison, which followed the defeat of Prince Charles Edward Stuart's followers at Culloden in 1746, he began work on 'The Lyon in Mourning.'
It includes interviews, letters, first-hand accounts and scraps of clothing fabric. These are from garments supposedly worn by Prince Charles, including some to disguise him as a maid of Flora MacDonald (1722 to 1790), the Jacobite heroine who aided his escape.
[Library reference: Adv.MS.32.6.18]
Volume three of the manuscript, dated 1747, was on display from March to September 2022.