No, this is false, the author does not accuse missionaries of stealing money in Crusades in 'War in Peace.' Instead, the author accuses missionaries of stealing souls in the novel. 'War and Peace' is a Russian novel written by Leo Tolstoy, published in 1867.
It is highly regarded among literary circles, and regarded as Tolstoy's best literary accomplishment, alongside his novel 'Anna Karenina'. The novel is about the history of the French invasion of Russia and the impact of the Napoleonic era on Tsarist society through the stories of five Russian aristocratic families, which involves accusing missionaries of stealing souls.