A school's atmosphere is very important. It determines whether you'll feel comfortable and whether you'll find your niche.
For this reason, many African–American students are unsure whether to attend a Historically Black College or University (a school specifically established to serve black students) or one that is more racially mixed.
You can be successful at either; it's an individual choice.
Predominantly black colleges and universities have a student body that is more than 50 percent black (most HBCU are predominantly black, but not all predominantly black schools are HBCU). There are also schools that have plurality of black students, meaning the largest segment of the student population is black, though black students do not make up the majority.
If your goal is to be around other African–Americans, you are not obliged to attend an HBCU. Even students of schools with smaller black populations join all-black fraternities or sororities, form a Black Student Union and live in African–American dormitories.
You should consider the environment for African–Americans at any college before you apply. Don't rely solely on the materials sent to you by the admissions office–do your own research. The U.S. Department of Education tracks statistics about minority students. Finally, visit your prospective colleges and talk to plenty of students (especially but not only African–American students).