Race identification, labeling, is all based in reaction; from it's very inception. Reaction to 'difference,' an unknown, and with lack of knowledge. This is true of all prejudicial choices.
'Race' as such, never really mattered. The reaction to such differences with misunderstanding did and still do, though potentially lessened over history.
Addressing 'race' is starting at a point further into the subject than starting at a true beginning point, i.e. "What causes reactions that became known as 'race' identification"? A: Lack of knowledge. "Why did these reactions lead to decisions based on incomplete information?" A: Again, lack of knowledge. "What will overcome callow prejudice?" A: Gaining knowledge and not relying on reactionary choices.