Our planet has been slowly warming since last emerging from the "Little Ice Age" of the 17th century, often associated with the Maunder Minimum. Before that came the "Medieval Warm Period", in which temperatures were about the same as they are today. Both of these climate phenomena are known to have occurred in the Northern Hemisphere, but several hundred years prior to the present, the majority of the Southern Hemisphere was primarily populated by indigenous peoples, where science and scientific observation was limited to non-existent. Thus we can not say that these periods were necessarily "global".