The collapse of the Hittite Empire in the Late Bronze Age has been blamed on various factors, from war with other territories to internal strife. Now, scientists have used tree ring and isotope records to pinpoint a more likely culprit: three straight years of severe drought.The collapse of the Hittite Empire in the Late Bronze Age has been blamed on various factors, from war with other territories to internal strife. Now, scientists have used tree ring and isotope records to pinpoint a more likely culprit: three straight years of severe drought.