Frances Calderon de la Barca was born in Scotland, settled in the United States, and in 1838, married the first Spanish minister to Mexico, a lively and well read lady. She spent the first two years of their marriage in the diplomatic circles of the restless, new republic, and from that vantage point observed its landscape, customs manners, and its political broil. The letters she wrote to friends and relatives for the basis of life in Mexico, which appeared in 1843 with a preface by the historian William Prescott, whose own conquest of Mexico, created a storm in the same year. The book was received enthusiastically by the public, and was deemed so accurate that it was used as a guide by American officers during the Mexican war of 1847.