The Islamic Golden Age, or the Islamic Renaissance, is traditionally dated from the mid-8th to the mid-13th century A.D. (sack of Baghdad) but has been extended to 15th and 16th centuries by more recent scholarship. During this period, artists, engineers, scholars, poets, philosophers, geographers and traders in the Islamic world contributed to agriculture, the arts, economics, industry, law, literature, navigation, philosophy, sciences, sociology, and technology, both by preserving earlier traditions and by adding inventions and innovations of their own. Howard R. Turner writes: "Muslim artists and scientists, princes and laborers together made a unique culture that has directly and indirectly influenced societies on every continent."