Thomas' history of Maryland focuses upon a number of aspects of Maryland's colonial history which, at the time of the book's original publication in 1900, had received scant attention. Thus, in the first chapter the author concentrates on Saint Clement's, Maryland, the precise place of the first landing in St. Mary's County. In fact, a third of the book is devoted to Maryland's first capital, St. Mary's City, and its surrounding county. Here the genealogist with 17th-century Maryland ancestry can benefit from a discussion of the laying out of the city, the founding of the Catholic Church in Maryland, the Calverts and their descendants, Governor Calvert's manors, early civil divisions, and more. In addition, the author has included an oversized topographical map of St. Mary's City showing the location of principal lots and homes.