What Caused the Black Death?

There was an understanding in the fourteenth century, evident in the writings of fourteenth century italian lawyer gabriel de musis that the black death had struck throughout the known world. But there's obviously something lacking here, and it would be lacking for some time in human attempts to understand the black death's origins. The plague afflicted the indians. In india, it weighed upon the send it seized with its hand and insnarled even the land of the ozbeks. And then he continues, the plague increased and spread further.