The process of ethnic identity development is similar to the process of identity development in general. Often the precipitating event involves an experience during which the individual encounters prejudice and becomes aware of his or her group's under-representation in some activity or setting. Following this crisis, individuals engage in a period of exploration during which they immerse themselves about their ethnic heritage. I am interested in knowing more about how this process of self-exploration leads to increases in self-esteem?
I would look at Jennifer Crocker and Brenda Major's paper in 1989, Psychological Review, entitled "Social Stigma and Self-Esteem: The Self-Protective Properties of Stigma" which focuses on how being the target of social stigma can actually be protective of one's self-esteem. It's not precisely what you're discussing but it comes the closest in the literature I know and they're discussion and bibliography would likely be a good starting point. Hope this helps!