The Relaciones Geográficas are a remarkable testament to the efforts by the Spanish Crown to compile and systematize basic information about its New World colonies. Beginning with a questionnaire of 50 items in the 1570s (later ballooning to more than 300 in the 1580s) regarding a wide range of natural, cultural, and demographic phenomena, the administrative responses provide an extraordinary accounting of peoples and places encountered in the process of conquest and colonization. While they were given out in order for the Spanish to govern more effectively, they can now be considered an early statistical study of the New World.

This collection consists of manuscript copies of most of the surviving Relaciones Geográficas known at the time (1970s), personally garnered from the General Archive of the Indies (Seville), major University Libraries, and other sources by Edwards. Also included are Edwards' descriptions, notes, and analyses of the materials, reprints of his publications, and ancillary materials, primarily reprints of significant scholarly treatments of the Relaciones Geográficas and their context. Especially noteworthy are papers of historian Howard Cline, long-time Director of the Hispanic Foundation of the Library of Congress, whose interest in the Relaciones Geográficas is reflected in his publications, and especially in a copy of his card catalogue of relevant documents from the General Archive of the Indies.