Also, a bunch of stuff that seems super-old actually isn't. There were still lions in the Caucusus until the 10th century... CE, not BCE. A thousand years earlier they lived in Thrace, too. There were still some wooly mammoths alive when the Great Pyramids were being built.
Similarly, living history can sometimes reach closer to the modern day than one might appreciate. There were (probably—some of the stories lack documentation) a few people born into legal chattel slavery in the US still alive while Martin Luther King, Jr. was active. The "Old West" and settler/Western Expansion days were still very much in living memory when early western radio serials and films were made, so it's entirely possible (likely, even) that a couple honest-to-god gunslingers (rare though they may have been, and as unlike their film counterparts) or victims/perpetrators of settler/native violence sat down and watched romanticized Westerns on the big screen. Shane is set in 1889 and came out in 1953. Lots of people alive during the fictionalized events of the film were still alive then. At least a few people who fought in or witnessed actual fighting in the Civil War likely watched Keaton's The General in a movie theater, or (more ominously) Griffith's The Birth of a Nation.