Allah clearly encourages us to knowing one another as stated in the verse. One of the ways of knowing other people and races is marriage.
Also, Prophet Mohammed (PBUH) Married to different women from different races and tribes and religion
O mankind, indeed We have created you from male and female and made you peoples and tribes that you may know one another. Indeed, the most noble of you in the sight of Allah is the most righteous of you. Indeed, Allah is Knowing and Acquainted. [Quran 49:13