covered about and included thirteen mounds near the Ohio River. Some of these mounds were built for ceremonial and cosmological purposes. In addition to the mounds, the Mississippians constructed structures and a defensive palisade (stockade) made of wattle and daub with walls and punctuated with bastions. This settlement was the largest-known town of its time in what became present-day Indiana. Scholars believe the town may have had as many as 1,000 inhabitants at its peak, which Indiana archeologist Glenn Albert Black estimated to be about 200 households. Archaeologists believe that the Angel community existed from around AD 1100 to around AD 1450, although estimates for the site vary from AD 1000 to AD 1600. Carbon dating of the community indicate it was developed as early as AD 1200 and as late as AD 1500. The Mississippian people abandoned the Angel site long before European contact; however, it is not known for certain why the Angel civilization declined. Scholars have speculated that it was potentially due to environmental factors, such as an extended regional drought that reduced the maize (corn) surpluses, and resulted in increasingly scarce natural resources that had once enabled the concentration of population. In addition, the people may have been overhunting, and reducing forests through the consumption of wood for constructing buildings and making fires. Archaeologists also theorize that with the collapse of the Angel chiefdom by AD 1450, many of the site's inhabitants relocated downriver to the confluence of the Ohio and Wabash rivers. A separate Late Mississippian cultural group subsequently emerged that archeologists named the Terminal Mississippian Caborn-Welborn phase (AD 1400 to AD 1700). Subsequent settlement Angel Mounds scholars believe that the Mississippians abandoned the site by AD 1400, and the Ohio River valley by AD 1650. In the eighteenth and nineteenth centuries, groups of other native peoples, such as the Shawnee, the Miami, and other historical tribes moved into the Ohio River valley from the east over the next 150 years. European explorers and traders subsequently arrived in the area. Anglo-American settlers who migrated to the area from the east and south remained to farm the land. Both the Native Americans and other settlers were attracted by the rich soil and temperate growing season. Mathias Angel (1819–1899) was among these settlers. In 1852 he began purchasing farmland that also included the archaeological site. The Angel Mounds Historic Site is named after the Angel family and