Like many at that time, his interactions were mostly within the white community.

white 在这里是形容词，指"白人的"，特指欧洲裔人种。在英语中常用来指代白人群体或白人文化。 community 指"社区、群体"，表示具有共同特征或居住在同一区域的人群。white community 特指由白人组成的社群或生活圈。