They may not actually capture the facts as they occurred, and very likely most of them don't present an accurate picture at all of what really happened. Most of the stories, battles, events, are related not objectively but from a very biased, personal and emotional point of view. Then they would then have been embellished extensively by people who subsequently picked up the song. Names, places, all kinds of things change. "Mattie Groves" becomes "Little Musgrave". "Fyvie" gets changed to "Fennario" and the captain's name changes from Ned to Sweet William. The "Road to Dundee" gets changed to the "Road to Sweet Carnloch Bay". What comes down to us are not the facts, but the essence, of the collective human condition through the ages. I think of a traditional song as almost like an abstract or impressionist painting. Suddenly you get a glimpse, an impression, of something that happened and the impact it had on someone long ago. And very often, it strikes an answering chord in your own psyche. At least that's how I view it. By the way, I don't know if the events related in "The Golden Vanity" really happened but that's one of my favorite ballads. (And that's another example of how innacurate the songs are - I've heard the enemy called both "the Spanish enemy" and "The Turkish Reverie". Who knows which one it was originally. Also I've heard that the captain was actually Sir Francis Drake (or it might have been Walter Raleigh).