Cripes, you're just not asking the right old timers!
Keweenaw means "place of crossing" in the native american dialect. Sort of like "portage" in our language.
Before the european-american settlers arrived, the area between Houghton and Hancock was a mix of swamp and some solid ground and was an area that could be crossed via portage with a canoe.
Not long after the copper boom up here started, that swampy area was dredged and made navigable for the ships to come through and service all the mills that were popping up on the Torch and Portage Lakes.
Hence, Keweenaw Peninsula!
-John