The book itself is divided into two parts: the seventeenth and eighteenth centuries. Chávez himself admitted in his Introduction that the family histories in the book do not necessarily conform perfectly to these divisions. Chávez discovered two distinct Spanish colonizations of New Mexico. The first colonization occurred in 1598 under the leadership of don Juan de Oñate. In 1680 Pueblo Indians revolted against Spanish rule and the Spaniards were forced out of New Mexico. In 1693 Diego de Vargas led a second group of families into New Mexico to re-colonize the province.