out the villages around an open oval central plaza, surrounded by circular and/or rectangular domestic structures facing the plaza. The arrangement of buildings in Fort Ancient settlements is thought to have served as a sort of solar calendar, marking the positions of the solstices and other significant dates. the people began to build low platform mounds for ceremonial purposes, and many villages added defensive palisades to their boundaries. The plaza was the center of village life: the place where ceremonies, games (such as chunkey) and other social events were held. The Late Fort Ancient period from 1400 to 1750 is the protohistoric era in the Middle Ohio Valley. During this era, the formerly dispersed populations began to coalesce. The Gist-phase villages (1400 to 1550 CE) became much larger than during the preceding period, with populations as high as 500. Archaeologists have speculated that the larger villages and palisades are evidence that after 1450, warfare and intergroup strife increased, leading the people to consolidate their villages for better protection. This era also showed increased contact with Mississippian peoples; some of whom may have migrated to and been integrated into Fort Ancient villages. The Madisonville horizon of artifacts after 1400 includes relatively high proportions of bowls, salt pans, triangular strap handles, colanders, negative painted pottery, notched and beaded rims, and some effigies, all items and styles that are usually associated with the Mississippian cultures of the Lower Ohio Valley, at sites such as Angel Mounds and Kincaid Mounds. These sites were abandoned during this time period. During the Montour phase (1550 to 1700), the people inhabited their villages year-round, although less densely in the winter than in the summer months. This may indicate that during the winter, family groups and hunting parties may have returned to the regions previously occupied by their ancestors. Such a pattern was observed during historic times, for example, among the Miami and Potawatomi. By their trading, the Fort Ancient people had access to European trade items, such as glass, iron, brass, and copper, which have been found as grave goods at sites such as Lower Shawneetown and Hardin Village. Such artifacts appeared and were used in the area before the arrival of European explorers or settlers. Although the Fort Ancient peoples did not encounter Europeans at this time, they, like other groups in the interior of the continent, may have suffered high fatalities from their diseases, transmitted