From what part of spain did most conquistadors come from?

from what region did the spaniards who settled in the americas come from?.. im mainly interested in those who who settled in the carribean.. want to know because where my families from in dominican republic(el cibao) they have a distinct dialect.. they substitute the r's for i's.. i hear a tad bit of this in andalucian spanish in flamenco.. ive also heard a bit of this accent with jorge ramos, a uruguayan football(soccer) yst for espn deportes("Jorge ramos y su bandaa" lol).. is this dialect a product of romani(gypsy) influence?..