Dated to 98 (Ger. 37.2) and describing the origins, religion and customs of the Germani, an ethnic group said to inhabit northern central Europe, Tacitus’s Germania is the only entirely ethnographic ancient text extant (ancient ethnographies tend to be a subsection of primarily historical or geographical texts). The work, however, does begin with a brief description of the geographical parameters of “All of Germania” (Germania omnis, a verbal reference to Julius Caesar’s Gallic Wars, which begin Gallia est omnis). The Germania is also strongly influenced by Caesar’s comparative ethnography of both Gauls and Germans (Gallic Wars 6.11-28). Tacitus …
Evans, Rhiannon Menai. "De origine et situ Germanorum ". The Literary Encyclopedia. First published 28 December 2009; last revised 30 November -1.
[http://www.litencyc.com/php/sworks.php?rec=true&UID=13475, accessed 27 April 2015.]