Some historical works can be copyrighted, such as Steamboat Willy, but there are many others that cannot, like the works of Shakespeare.
As for historical events, a couple years back, a woman sued Steven Spielberg because she claimed the film Amistad was based on her book. Spielberg claimed the film was not based on her book, and the events that occurred actually did happen. A judge agreed, ruling the woman cannot own a historical event.
The original post I was replying to mentioned copyrighted material being put into the Mormon genealogical database. If a copyrighted book says that John Doe was born on May 1, 1800, is it a violation of copyright to put that historical fact into a genealogical database?