A growing body of evidence indicates a period of severe drought that lasted about 150 years, from the mid-13th to the late 12th century BCE; see Eric H. Cline, 1177 B.C.: The Year Civilization Collapsed, rev. ed. (Princeton: Princeton Univ. Press, 2021). It is likely that mobile societies were able to adapt more easily than city dwellers to changes in the availability of water and pastureland.