To harbor year-round human settlement prior to the 1870s?

Does "to harbor year-round human settlement prior to the 1870s" mean "about the fact that it (the valley) had human settlement living there full time all year round prior to the 1870s"?

Context:

The valley is thought to have been named after David (Davey) Edward Jackson who trapped beaver in the area in the early nineteenth century. Though used by Native Americans for hunting and ceremonial purposes, the valley was not known to harbor year-round human settlement prior to the 1870s. Descriptions of the valley and its features were recorded in the journals of John Colter, who had been a member of the Lewis and Clark Expedition. After returning to the Rocky Mountains, Colter entered the region in 1807 in the vicinity of Togwotee Pass and became the first white American to see the valley. His reports of the valley, the Teton Range and the Yellowstone region to the north were viewed by people of the day with skepticism.