Since works created prior to 1923 are now in the public domain in the US, searching for images using keyword and “no known restrictions” in the Library of Congress’s Prints and Photographs Catalog will yield a lot of older photos. But not all are pre-1923. For example, consider these:
That’s Jackie Kennedy on her wedding day, Sept. 12, 1953 [LOC, LC-USZC4-4332 ] and Sir Winston Churchill with his son and grandson preparing for the coronation of Queen Elizabeth II in 1952 [LOC,LC-DIG-ppmsca-05370]. Both photos are by Toni Frissell.
Or these images of WWII:
1943 US Navy photo of torpedo bombers [LOC, LC-USZ62-113551]
Wreckage of USS Arizona, Pearl Harbor, Hawaii, December 7, 1941 [LOC, LC-USZ62-132048]
And then there are so many subjects that don’t change much over time.