The Thunder Bay National Marine Sanctuary focuses on understanding the region's "maritime cultural landscape." A cultural landscape is a geographic area including both cultural and natural resources, coastal environments, human communities, and related scenery that is associated with historic events, activities, or people. In other words, while the shipwrecks of the Thunder Bay region are the most obvious underwater cultural resource, the sanctuary will put the shipwrecks in the larger context of the region's lighthouses, lifesaving stations, shipwreck salvage operations, and maritime economic activities.

The maritime history of the Thunder Bay region is characterized by the use of, and dependence upon, natural resources. These resources include animal furs, fisheries, forests, farmland, and limestone. The first recorded use of natural resources for transportation, food supplies, and recreation in Thunder Bay was by Native Americans during the Woodland period. European activity probably originated with the efforts of Native Americans and French traders to locate and trap beaver during the 1600s.

Trading and supply boats routinely passed Thunder Bay on their way to outposts at Mackinaw, Sault Ste. Marie, and Green Bay. In 1679, LaSalle's GRIFFON became the first major European vessel to pass by Thunder Bay, and many others were to follow. The need to transport supplies to northern frontier posts stimulated construction of small brigs, sloops, and schooners. Thunder Bay accumulated a large collection of shipwrecks because of its strategic location along shipping lanes, and because the bay and nearby islands provided shelter for vessels during inclement weather.