These African-inspired artworks were created for the tabletop RPG Spears of the Dawn (from Sine Nomine Publishing). They are part of an art, map and layout pack released into the public domain (and available for download from here).
This set is by Ian MacLean and depicts:
The publisher writes:
The art in this resource pack was provided by the talented hands of Andrew Krahnke, Earl Geier, Ian MacLean, Luigi Castellani, Miguel Santos, Nicole Cardiff, and Sara Mirabella. At the agreement of the artists and under the terms of its commission, it is intended for the public domain, and may be used by anyone for any purpose desired. As a matter of courtesy, I would request that you leave the artist's name attached to the file and credit them in your work.
The files in the InDesign and Maps folders were created by me and are also in the public domain and available for any person to use as they see fit. No credit is necessary should you find them useful.
If you choose to redistribute this resource pack, please keep the files together, in order that other users can more easily confirm that they are, in fact, public domain works and available for their use. If that is impractical, you should likely reference the work as being released into the public domain by Kevin Crawford of Sine Nomine Publishing on January 22nd, 2013, so they at least know who to ask to confirm its provenance.
Kevin Crawford
Sine Nomine Publishing
sine.nomine.pub@gmail.com