The Haya (or Bahaya) are a Bantu ethnic group based in Kagera Region, northwestern Tanzania, on the western side of Lake Victoria. With over one million people, it is estimated the Haya make up approximately 4% of the population of Tanzania. Historically, the Haya have had a complex kingship-based political system. Agriculture, particularly banana farming, is central to Haya economic life. They are credited with the independent development of carbon steel dating to 2000 years ago using pre-heating techniques.