Complex sentence: As an advocate of Black nationalism, Walker also jointly edited the newspaper, "The Equator", with his brother and published the book, "Our Home Colony", in 1908 to explore ideas about emigrating back to Africa.
Split into simpler sentences: As an advocate of Black nationalism, Walker also jointly edited a newspaper, "The Equator", with his brother. He published a book, "Our Home Colony" (1908), to explore ideas about emigrating back to Africa.