Oily Men in the Carnaval Parade - Help Please

  Okay, I now have almost 300 photos edited from my winter in the Dominican Republic, and I'm about to start compiling the Photo Journal, the coffee table book that has been the object of this cultural project.
  But I need your help.  I feel that I have a working knowledge of the culture from living there for extended periods of time, but I've been stumped by a couple of things and would like to have my readers help me gain some background information on these things before I begin on the book.  My goal is to have the book ready by the end of April.
  Here's one of my puzzles:  While shooting the Carnaval Parade in the town of Samana, I photographed some guys who were covered with oil - at least I think it was oil.  I touched the one guy and sure enough I ended up with a black smudge that I had to stop and clean off before handling my camera any further.
  Besides the oily guys in this entourage, there were also a guy with his hands bound in cuffs, a "tyrant" behind them flogging them with a branch, and they were taking donations with a big can and a bag.
  What is the back story on this tradition?  What do these guys represent?  If some of you would do some research and link me to the information, I'd be very thankful.  If you come up with some good stuff, I'll mention you as a contributing researcher in the book.
  Email me or make a comment here on the blog with the links.  My email is: rasims@juno.com
  Thank you!
Oh, here's the link to the photo gallery I'm working from for this book:
http://simsshotsphotography.zenfolio.com/p391431575

Okay, folks, I've had some people help me out with some great resources.  It turns out that Los Africanos pictured here are representing the original African slaves who were brought to the Dominican Republic and became part of the Dominican heritage.  They take donations from bystanders who don't want to be hugged by them!

The Seaside Economy

  There are markets throughout the community.  Everybody's trying to make a living in a mostly agricultural area that is strengthened with a bit of tourism.  Some work with the tourists to serve as guides for ATV safari's, or paint oil paintings at night under a single light bulb, hoping to make a sale to a tourist in a few days.  This fellow runs a fruit and gift market in a shack along the road to one of the popular beaches.  These guys have to learn second and third languages in order to do well; there is a mix of tourists from Canada, Germany, France and a very few Americans.  When we stopped to get some pictures at his shop, he came out asking if I wanted to speak in Spanish, English, German or French.  Gotta hand it too em', they work hard to make a few bucks.

  I've been home for 10 days now and have edited about 75 photos for my gallery and photo journal.  I'm hoping to have all of it ready by April.  Start viewing the photos that I have posted already on my photo website. This link takes you right to the Dominican Culture gallery:

  http://simsshotsphotography.zenfolio.com/p391431575