I will rant a bit on history as it appears on cable. I say cable since the broadcast stations don't feature much in the way of documentary material except PBS. Now that I have been writing history somewhat professionally for about ten years I think I'm in a position to comment on this genre. There is some good, lots of mediocre and some poor content. The viewer has to remember that programs are generated by producers who seek to generate a profit from selling something, anything, to the cable companies. I have never heard of a program that did not get sold.
The lead in cable history, as you can guess, is held by The History Channel which has branched off into all kinds of documentaries like The Axe Men and Modern Marvels. When THC first aired it was the World War II channel. The History Channel is now part of the same company that does A&E, Biography, and other History Channels. As viewership grew more content became available.
The first thing to remember about anything presented on television is that film and video are visual media. If you don't have a picture, you have to come up with one. That's one reason World War II was a natural starting point for televised history even back as far as The Twentieth Century and Victory At Sea in the 1950s. Ken Burns took the business to a new level with The Civil War in the 1990s. He developed a way to make still images move and brought to life that sad and critical moment in American life.
There are endless miles of film footage in official archives all over the world. Most of it was generated by government-paid soldiers and sailors and lie in the public domain. No royaly fees need be paid, an important feature of any commercial project. World War II is a great story: evil empires rise up to murder and enslave millions to be beaten back by young, brave, freedom-loving GIs (of course, the Sovs, the Brits, and others bled too, but the American producers decide what gets presented). Probably the two most used pieces are Stukas diving onto Poland in 1939 and the U.S.S. Arizona blowing up at Pearl Harbor. Too bad the survivors don't get residuals.
As THC grew more popular, the documentarians reached further and further into the vaults for footage to illustrate something, anything. Barring the usual difference of opinion between historians and predictable error the scripts appear to be sound academically. Alas, while the viewers watch footage they probably aren't listening to the narration. I think the producers know this so they feel free to show images totally unrelated to the script.There seems to be some union rule that writers and historians were not permitted to work with editors to point out that the airplanes in question are American and not Japanese or that the shots represent something five years from the event being described. That's the first giveaway to a bad documentary, but only geeks like me who can distinguish a B-17 from a B-24 or a Zero from a Dauntless really cares. This has gotten better in recent years I think.
The simplest documentary is public-domain archival film and narration. Then the producers added talking heads, historians, eyewitnesses, and anyone with something to say. This added an important dimension to the genre since the information was usually correct and the viewer tended to pay attention to what was said. The historians typically know their stuff. The eyewitnesses, mostly aging veterans, know what they know strained through the filters of time and perception. The last category is some descendant or any old person who knows what is written in the history books, but did not see it themselves. The crawl under their clip credits them with being a son or niece or simply being alive at the time. Talking heads need to be delivered in short breaths to keep the story line moving and to keep the viewer away from the remote.
Next the producers added footage of meticulously attired reenactors marching into battle. Reenactors are hobbyists who dress up like historical military units and even specific personages. They gather on weekends and camp out and march and have a wonderful time. The most numerous hobbyists are Civil War reenactors. Ted Turner used thousands of them to make the movie Gettysburg a visually stunning experience that credibly gave us an important historic event (but the soldiers were all too old and too fat). The guys who dress up as Abraham Lincoln, U.S. Grant, and Robert E. Lee deserve special mention. It works for television and there are excellent, if drawn out, histories of the Civil War. This approach works well in any period and as long as actors don't speak, you don't have to pay them as much.
The spinoff of this is The History of Sex where there are plenty of reenactors available and they aren't too old or too fat. Scenes of writhing bodies, appropriately blurred, are spliced in with more talking heads and full-color depictions of love in Egypt, Greece, and Rome. I would love to have been around the studio as that one was pulled together.
Probably the last, best iteration, in my view, is the two-part series on Paris 1919. Using lookalike actors in period dress who speak the correct languages, the producers give us an accurate and somewhat compelling account of a critical and often downplayed period in history. At the end of The Great War (World War I) the European allies carved up the world and hammered Germany economically. This planted the seeds for the rise of Facism ten years later and then World War II twenty years and four months later. Just about everying wrong about the 20th Century can be traced to the Treaty of Versailles and the divisions of colonial spoils. People die today because of these decisions. Kudos from me to Paris 1919.
Computer animation has added a great deal to understanding history. Moving arrows on maps have evolved into three-dimensional representations of battles that might remain misunderstood but for technology. This is not cheap to do accurately.
You can tell when the producers are focused on viewership and not history when they leave you hanging just before the commercials and retell the story at the end of the commercials. That's because the producer's biggest enemy is the remote control. The commercials come on and you look for something else. Have you noticed that the other channels have commercials at that same point in the hour? By crafting history around the remote a thirty-minute story can be stretched to an hour. The hour blocks are easier to fill. The editors recycle footage and narration and you don't get the whole story until the very end. It seemed to take forever to document that fact that a minesweeper was sunk by a then-secret German mine.
I have one documentary to my credit, but it wasn't crafted around commercial breaks. It was designed as history and the story unfolds coherently. The editors did an excellent job matching appropriate still shots and narrators and contemporary footage to the narrative so I know it can be done.
One of my favorite history programs is The American Experience and the historians appear to have taken control. They seem to have hit on the right blend of archival footage and talking heads to tell a story that remains both accurate and compelling. And anything by Ken Burns is worth a watch, but his work requires some dedication to follow each series.
End of rant