The Pueblo I-IV periods refer to the four distinct cultural phases of the Ancestral Puebloan people, who lived in the Four Corners region of the United States. The Pueblo I period (AD 750-900) is characterized by the emergence of large villages and
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The Pueblo IV period (1350–1600) was the fourth period of the Ancestral Puebloans in Oasisamerica. At the end of prior Pueblo III period, ancestral Puebloans living in the Colorado and Utah regions abandoned their settlements and migrated south to the Pecos River and Rio Grande valleys. As a result, pueblos in those areas saw a significant increase in total population.