Final answer:
Around 1300 AD, Pueblo lands condensed due to environmental, social, and external pressures, including the Great Drought, insularity, new irrigation practices, religious turmoil, and the migration of new peoples, leading to abandonment and eventual assimilation into modern Pueblo cultures.
Step-by-step explanation:
The condensation of Pueblo land around 1300 AD is attributed to a confluence of challenging factors. The Ancient Puebloans faced significant environmental stress due to a 300-year long Great Drought that affected North America, driving them towards more insular communities, less trade, and more intensive agriculture with advanced irrigation techniques. Furthermore, archaeological findings suggest that religious turmoil impacted their ceremonial structures, featuring deliberately set fires and boarded-up windows and doors. Additionally, the introduction of new peoples to the area added external pressure. Ultimately, many Ancestral Puebloan communities, such as at Mesa Verde, were deserted around 1300 CE, and historical evidence and Pueblo oral traditions suggest that the populations moved south, assimilating into what became modern Pueblo cultures.