Where are predatory publishers based?
There is a study by Shen and Björk (2015) which includes a figure (Fig. 6) showing 


  the distribution of the publishers across geographic regions. The distribution is highly skewed, with 27 % publishing in India.




Figure 6:



(the figure's license: Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made)