The 1930s brought an increase in planning efforts, but the park was still managed from a distance and functioned more like a community park than a unit of the National Park Service. Through the 1960s administration of the monument was either combined with Glacier Bay National Monument or was under the purview of the Superintendent of MT. McKinley National Park.
The 1940s began with the arrival of Ben Miller, the park's first full time resident custodian. The park, like the rest of Sitka, felt the effects of the World War II buildup. Evacuation of nonmilitary personnel and disruptions to civilian travel greatly limited visitation. The park was transferred into military hands during 1942 and briefly occupied for defense purposes. It was formally returned to the Department of Interior in 1947. More significantly, a series of massive military construction projects triggered the removal of massive amounts of gravel from the park's river, shoreline and estuary. Environmental impacts from the gravel removal proved to be a major resource issue for decades to come.
In 1965, a new visitor center, the park's first real visitor facility, was completed. It provided room for exhibits and demonstrations of Alaska Native arts and crafts. In 1969, in an agreement that was groundbreaking at the time, the Alaska Native Brotherhood assumed control of the demonstration program and established its focus on Southeast Alaska Native cultural arts. Known today as the Southeast Alaska Indian Cultural Center, this successful program celebrated its 30th anniversary in January 2000. Another aspect of the park facility that was clearly ahead of its time was its display of remarkable Tlingit artifacts. Many of the objects in the collection were loaned or donated by local clans under agreements designed to insure ongoing traditional use.
In 1972, the monument's name was changed to Sitka National Historical Park and its boundaries expanded to include the Russian Bishop's House, a National Historic Landmark. Acquisition of the house brought more emphasis to the Russian American focus of the park and involved the park in a lengthy restoration project.