 In addition, it manages the process for applications within the state for additions to the National Register of Historic Places.The Illinois Historic Preservation Agency (IHPA) was created by State law in July 1985.What was the agency's oldest bureau, the Illinois State Historical Library, was created in 1889, but the origins of the agency could be said to date back to the state's involvement in building and caring for the Lincoln Tomb in Springfield, Illinois, in 1865.