Factual error: Considering it is the Depression, it is highly unlikely that the family would have any electricity in The House. With maybe the exception of a lamp or two, as rural folk typically didn't have such accommodations in 1930. Yet every room has some form of fancy lighting display.
The Carnival - S1-E3
Factual error: After John-Boy reads the scary bedtime story to Jim-Bob and Elizabeth, when Elizabeth is lying in bed she's holding her Raggedy Ann doll, and in the closeup we can see the doll's Knickerbocker tag. This episode takes place in 1933 (the Chicago World's Fair is mentioned at the end), and the Knickerbocker Toy Company created this doll in the late 1960s. (00:09:30)
The Bicycle - S1-E23
Factual error: While Ann is on the Walton's swing telling Curtis that he deceived and lied to her, when Curtis gets back into his car, a modern vehicle is visible at the right side of the screen, which is inappropriate for the time period. (00:46:10)
The Townie - S1-E24
Factual error: After John-Boy and Sarah's date at the double-feature, during the ride back home when John-Boy tells Sarah that there's nothing to makeup and he's not mad, through the windshield 1970s vehicles are parked directly ahead of John's pickup truck. (00:08:25)
Factual error: After Olivia realises she has polio, when John goes downstairs the radio is on and we hear an excerpt from President Roosevelt's fireside chat about upcoming Labor Day. The problem is this aired on the radio right before Labor Day in 1936, but Olivia contracts polio very early 1934. (00:22:35)
Factual error: When John-Boy and Jason walk into the theater, there's a poster for the movie Breakthrough, released in 1950, which is about the Battle of Normandy that didn't even happen until Summer 1942. This episode was set in early 1934. (00:50:55)
Factual error: When Mary Ellen brings G.W. into the woods to practice dancing together, she opens up a magazine and shows him a movie still of Fred Astaire and Ginger Rogers. The problem is the photo is a still from Fred and Ginger's dance in the movie "Swing Time" (at 00:28:00 within that movie) which premiered August 1936 (and was filmed that year), but this episode takes place more than two years prior, in early 1934. (00:59:20)
Factual error: When Olivia gets polio, she is at home. John is allowed to stay with her 24/7. It seems unlikely that the doctor, even if not taken to hospital, would allow John to stay in the room and risk contamination.
Factual error: The Literary Digest Sheriff Epp is reading in Godsey's store is dated Aug 1936, when only a year has passed since the show's inception at 1932.
Factual error: The Woman talking with Mamie and Emily about the jams is wearing 1970s large framed glasses. (00:33:15)
Factual error: After Ethel Richardson unwittingly reveals to Miss Pollard that there's a special meeting of the school board, when it cuts to John's truck returning home from the meeting, at the start of this shot a modern black car is visible at the top, right corner of the screen. (00:34:35)
Factual error: When Elizabeth asks Zeb how Vanessa can be happy, Zeb has his old catalog with a bunch of flower seed packets on his lap, and as they both hold up the packets, particularly Elizabeth, the modern Universal Product Codes are at the back of the packets. The UPC did not exist until many years later. (00:10:05)
Factual error: After Jason tells Olivia that he's giving up playing his music because he doesn't think he has a choice, when it cuts to the exterior shot of the rooming house, the vehicle parked in front is modern. The same type of thing happens later, when John rescues Pip from the airfield there are modern vehicles, etc, on the street in the background. (00:34:30 - 01:29:30)
Factual error: Jim Bob is shown communicating with friends in the UK via amateur radio. During WW2 amateur radio operators in most countries were prohibited from transmitting any signals until after the end of the war.
Factual error: While Jason is practicing piano at the Dew Drop he hears the horn playing outside, then when he walks out of the back door he sees Josh on the trumpet, and in the first shot of Josh we see a blue modern vehicle moving behind the bush, at the top left corner of the screen. (00:05:00)
The Return - S6-E20
Factual error: The year is 1940, and in the opening shot (as the name Richard Thomas appears on the screen) we have a view of Lower Manhattan as seen from the East River below the Brooklyn Bridge, but the problem is some of the buildings we see did not exist in 1940, such as One Chase Manhattan Plaza, which did not begin construction until 1957. (00:01:40)
The Return - S6-E20
Factual error: Right before the scene with John-Boy and Daisy at the restaurant, there's a shot of Times Square, and two of the marquees advertise the 1946 movie "The Jolson Story," and the 1946 movie "The Best Years of Our Lives," and also reads "Picture of the Year" which it won at the 1947 Academy Awards, but this episode takes place in 1940. (00:05:30)
The Attack - S7-E18
Factual error: When Ike is in the hospital and is talking to John, he is wearing a plastic ID wrist bracelet for patients. They didn't start using them until much later.
Factual error: When Toni and John-Boy make a bet about who will locate Jason first John-Boy is holding a book, and just as they agree to the loser buying a bottle of champagne, this book's author and title are visible on the spine. That book is "A Pocketful of Rye" written by A. J. Cronin, and published in 1969, though this episode takes place in 1945. (00:30:35)
Factual error: After Cindy admits that she needs to know why she was put up for adoption, when it cuts to a clip of Washington DC with the Washington Monument and Jefferson Memorial in the background, we also see vehicles not appropriate for 1945. (00:14:45)
