Attic fans and swamp coolers were all the rage in North Dakota and Minnesota in the 50s and 60s.
Before we moved to this old house, we lived in an old house with an attic fan. It worked really good. The old-timers knew how to build houses that wouldn’t cook the occupants when it got hot. :-) Our house in FL in the 50’s was built with concrete blocks. It was hurricane safe (mostly) and cooler than a frame house.