The Summer Fields - LP Fergusson

At the dawn of the eighteenth century, smallpox is ravaging England, but dairy maid Elen Griffiths is blessed with immunity. After she's sent away to Duntisbourne Hall to nurse the ailing Viscount Mordiford, though, the blessing feels like a curse. There, Elen finds a horribly afflicted patient, but she also discovers a friend in a charming valet.
 
However, before long, sinister forces threaten Elen's life and honor. After she's rescued by the man she's grown to love, she flees the country with the English army, not knowing if her affections are returned.
 
Across the Channel, Elen finds purpose serving as a nurse during the Duke of Marlborough's campaign. Surrounded by the horror and confusion of the brutal war against the French, Elen is reunited with her love on the eve of the Battle of Blenheim—and learns that his feelings mirror her own. But as the bloody conflict rages and a dangerous figure from Elen's past returns, a moment of joy may be all they ever know . . .