I don't see how this adds to the conversation. Also, Argentina and Uruguay have similar racial composition & as far as I can tell see themselves as the same people of the Rio Plata.
http://www.indexmundi.com/uruguay/demographics_profile.html http://www.indexmundi.com/argentina/demographics_profile.htm...
Uruguay have 12% non-white, Argentina only 3%
That's not what I would call "similar".