The Adventurers // Royal Gamble — Jane Aiken Hodge

Young Sonia von Hugel was forced to witness the destruction of her family and home during Napoleon's retreat. Disguising herself as a boy, she fled from the marauders who were looting the countryside. Between the French and the Cossacks she was in deadly peril. But Sonia's first encounter with the enigmatic adventurer and card shark, Charles Vincent, penetrated her disguise and left her at the mercy of the stranger. Charles promised a life of excitement and thrills if she would stay with him. Suddenly Sonia had to make a choice between him and the terrible dangers that lay in wait for them both.
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UK Hardcover Edition

Retreating at last, Napoleon's army fights its way back towards Paris. In its wake: chaos, and the Allied pursuit. And two girls, Sonia and Elizabeth, who must make their way, somehow, to England. Is it wise to throw in their lot with Charles Vincent, a self-confessed adventurer? But what else can they do? And how far can they trust him?