Complex sentence: The Nuremberg race laws of 1935 classified as "racially acceptable" people with "German or related blood" all persons wishing to be a citizen of the Reich had to provide proof of their Aryan ancestry by acquiring an Aryan certificate.
Split into simpler sentences: The Nuremberg race laws of 1935 declared only people of "German or related blood" were eligible to be Reich citizens. All persons wishing to be a citizen of the Reich had to provide proof of their Aryan ancestry by acquiring an Aryan certificate.