Last ice age: did glaciers move South or move downhill?
Did glaciers move South or move downhill?

You are posing this as an either-or question. The answer is &quot;Yes.&quot;
The highest points above sea level in Manitoba, Minnesota, Ontario, Michigan, Wisconsin, Iowa, and Illinois are respectively 832 meters, 701 meters, 693 meters, 603 meters, 595 meters, 509 meters, and 376 meters. Central Canada and the United State's upper midwest are very flat.
Even the eastern parts of the US and Canada are relatively flat compared to the huge ~4000 meter thick ice dome centered roughly on Hudson Bay. Every direction was downhill from the peak of this ice dome. The ice flowed to the west to meet ice streams from the Rocky Mountains (and then turn north or south), to the north toward the Arctic Ocean, to the east toward the Atlantic Ocean, and to the south to meet warmer temperatures. The ice at the southern edges was much thinner, but it still was a downhill flow.