Newly-wed Harriet stands poised on the threshold of the adult world. Her husband, James, is setting off to join the Duke of Wellington's troops in Spain and left alone in London, Harriet is taken under the wing of Lady Wellington. While Harriet plunges into a new life of freedom at home, James faces the bloody reality of the battlefield.

As war rages abroad and England stands on the brink of change, Harriet and James face hope and heartache in equal measure. From the mantillas and palms of Seville to the gas lamps of foggy London, Tides of War returns us to the vivid, lost world of the past.