Here are clips from the movies Puttin’ on the Ritz (1930) and the “Bojangles in Harlem” number in Swing Time (1935):
Here are links to additional information about the Sape, the dandy phenomenon in the two Congos:
You may also be interested in this article about the Herero of Namibia, who transformed the dress imposed on them by German colonial forces into a distinctive style: http://www.slate.com/blogs/behold/2013/03/01/jim_naughten_documenting_the_herero_tribe_of_namibia_and_its_20th_century.html
It’s a shame that we all missed this exhibition at RISD, since it seems that men’s fashion is often neglected. I also recommend you check out the Related Notes to the right of the page.