Complex sentence: Their most famous leader (or "shaikh") during the 19th century was Rakan bin Hithalayn, who is still well known in Arabian tribal lore, and who was noted for his poetry as well as aptitude in battle against the Ottoman Turks.
Split into simpler sentences: Their most famous leader (or "shaikh") during the 19th century was Rakan bin Hithalayn, who is still well known in Arabian tribal lore. He was noted for his poetry as well as aptitude in battle against the Ottoman Turks.