Texas experienced a dark age (AD 536-700) and it was the same one they had in Europe and the rest of the Northern Hemisphere. There really were dark years, especially in the beginning with a series of large volcanic eruptions, mostly the Central American Ilpango series in the 6th century. So much dust was thrown into the atmosphere that the sun’s intensity was dimmed, causing frosty summers and acid rain that ruined the soil for decades all across the Northern Hemisphere. The acid rain released aluminum into the soil and water, creeping into the food supply, causing dementia and other neurological damage, which explains the irrational behavior associated with the dark ages. To make things worse it was a period of low solar activity, which has the effect of releasing some of the sun’s rays that cause diseases to jump to new forms. In some areas this meant smallpox, for Europe it meant Yersina pestis, the bubonic plague that killed millions. This was when the Western Roman Empire broke-up. In Texas, the dark ages were dark for the same climatic reasons, and the period is archeologically dark. Four major archeological studies from Central Texas report that the sediment formed during these years is empty of any human habitation. People had camped in these areas for thousands of years and would continue to occupy those sites after AD 700. But the people weren’t there anymore. The archeological record is more clear in the Eastern Woodlands (mostly the Mississippi Valley) where people scattered into small, family groups after the 6th Century climate catastrophe. They gave up village life for centuries. There may have been a disease that contributed to this fragmentation of peoples – Treponematoses – a terribly destructive disease that caused the face to crater, leaving disfigured marks on the skeletons. If the Texas Natives responded like Indians did in historic times when faced with smallpox and cholera, they broke into family groups and avoided the usual camping areas for fear of contagion. Around AD 700, the sedimentary record of human habitation continued in Texas and in the eastern part of North America, the Indians began to to try village life again.