During the first century of the Achaemenid Empire the royal family and nobles, often related by marriage, controlled the political and military positions in the elaborate imperial structure. This monograph, based largely upon the ancient Greek texts that provide patronymics and familial connections, analyzes the personal relations of 317 royal and noble men, women, and children. A brief historical sketch is provided for each, accompanied by references to the ancient Greek and Latin sources, and a limited number of ancient Persian sources, to provide extensive notations for further research. The Greek and Latin sources are analyzed for their historical merit and kingship is explored in detail. Study of the women and children of the royal harem includes issues of marriage, eunuchs, concubines, and pederasty. Both the political and military roles of the young men are examined, and prosopographical problems are also addressed.