Complex sentence: He is best known in the United States for his study of race relations, which culminated in his book', which was influential in the 1954 landmark U.S. Supreme Court Decision Brown v. the Board of Education.
Split into simpler sentences: He is best known in the United States for his study of race relations, which culminated in his book'. The study was influential in the 1954 landmark U.S. Supreme Court Decision Brown v. the Board of Education.