Complex sentence: His mother was Louisa Margaretha Neumann, of half German and Javanese descent; the younger Douwes Dekker was related to the famous writer, Eduard Douwes Dekker, author of Max Havelaar, who was his grandfather's brother.
Split into simpler sentences: His mother was Louisa Margaretha Neumann, of half German and Javanese descent. The younger Douwes Dekker was related to the famous writer, Eduard Douwes Dekker, author of Max Havelaar, who was his grandfather's brother.