The Dark Mile — D.K. Broster

Set during the 1745 Jacobite Rebellion, this is the third and final instalment of D. K. Broster's trilogy. The Dark Mile is the sequel to The Flight of the Heron and The Gleam in the North, completing the trilogy. 
The Dark Mile follows the intersecting fortunes of Keith Windham, the career soldier in the British Army, and Ewen Cameron, a young Highlander who will discover if it was worth it to leave his home and his bride-to-be to follow Bonnie Prince Charlie in his bid for the throne...