Complex sentence: The reputation of Durham City and Durham County schools, prior to integration, was that the most prominent people (white or black) attended Durham City schools and if you were white you attended Durham High School and if you were black you attended Hillside High School.
Split into simpler sentences: The reputation of Durham City and Durham County schools, prior to integration, was that the most prominent people (white or black) attended Durham City schools. If you were white you attended Durham High School and if you were black you attended Hillside High School.