Civilizational Declines During The Little Ice Age
The Little Ice Age is generally considered to take place between 1250 and 1850 AD. The AGW believers generally deny that the Little Ice Age was global, arguing that it was European. I've long thought it curious that non-European civilizations suddenly decline or even collapse at about the same time. For example, from reading works such as this, it appears that the Mississippian Moundbuilder civilization went into decline between 1200 and 1500--and thus before European contact can explain it. I also notice that this decline seems to be associated with substantial nutritional problems in the skeletons that have been recovered from the decline period. Population decline was already well under way when Columbus arrived, giving smallpox and measles to the Indians, who returned the favor with what now appears to have been an especially virulent strain of syphilis.
There seems to be considerable debate about whether droughts in the 1100s caused the decline of the Anasazi culture, or whether the decline is in the 1200s. This article argues for the second half of the 1200s as drought periods that ended the Anasazi culture--and seems to argue that the Mississippian Moundbuilder culture was impacted by these same weather pattern changes. At about this same time, in the mid-1200s, the Aztecs arrive from the Southwest into the Valley of Mexico (to the severe disadvantage of the locals).
While not everyone experienced the climate change in the same way, that North America was suffering a dramatic transformation in the same half century seems to argue that the Little Ice Age was global--not specific to Europe.