The Medieval Warm Period (MWP) also known as the Medieval Climate Optimum, or Medieval Climatic Anomaly was a time of warm climate in the North Atlantic region that may have been related to other warming events in other regions during that time, including China[1] and other areas,[2][3] lasting from c.;950 to c.1250
There was an extreme 50-year drought that started around 1130 AD that that is cited as being responsible for the decline of the Pueblo peoples at Chaco Canyon in northwest New Mexico (it is a really neat place to visit).
It's not impossible that drought could have been brought by medieval warm period, and resultant changes in weather patterns. I was mistaken in trying to connect the decline of the Chaco culture to the Maunder Minimum, that would have been 500 years too early (Maunder Minimum was middle 1600s, not 1100s), so it's more likely the Medieval Warm Period was responsible for the change.
PS - I was trying to figure out when I posted the blurb you responded to, thinking that I wasn't on line yesterday and posting to FR. It's August 19, but from 2016.