Factual error: In series 1, Sergeant Moss says he and most of his men served in the First World War, but none of them wear any medal ribbons. In series 2, Moss has suddenly acquired three medal ribbons, but they seem to be made-up and are not relevant to the First World War. From series 3, Moss is wearing the correct three service ribbons for the First World War.
Factual error: Chief Inspector Campbell has been sent from Belfast. Belfast at the time was policed by the Royal Irish Constabulary, which had no rank of chief inspector.
Factual error: Throughout the show bottles of liquor have sprout dispensers attached to them. Sprout dispensers were not invented until the 1960s.
Factual error: Filter cigarettes weren't conceived until 1925 and not in common use until decades later. No self-respecting gangster would have smoked them.
Factual error: Filter cigarettes didn't appear before 1935, but here everyone seems to be smoking them.
Episode #1.1 - S1-E1
Factual error: Thomas' record says he received the King's Medal for Gallantry in the First World War. There was no such medal. It would have been the Military Medal.
Episode #1.1 - S1-E1
Factual error: Ada is watching a movie and when asked "tell me the man's name" says "Rudolph Valentino." Valentino was largely unknown in 1919, only appearing in bit parts. She is also eating popcorn. This was not done in movie theaters until the 1930, unless you brought your own. Only street vendors sold popcorn.
Suggested correction: This is from episodes #1.2 and two separate mistakes. But being "largely unknown" doesn't mean she couldn't know his name. And who's to say she didn't buy the popcorn from a street vendor? You don't see others eating popcorn, so there's no suggestion she bought it there.
He used the name Rudolph Valentino for the first time in 1921.
That's not true since he was credited as Rudolph as early as 1917.
Episode #1.3 - S1-E3
Factual error: When attempting to arrest Grace one of the supposed IRA men proclaims that he is taking her into custody "on behalf of the Irish Free State." The term "Irish Free State" was not a term used by republicans or generally until the Anglo-Irish Agreement which led to the end of the War of Irish Independence and the establishment of the Irish Free State in 1922. Anyone representing the IRA would have, when speaking English, referred to the Irish Republic at that time.
Episode #1.3 - S1-E3
Factual error: One of the men who approaches Tommy claiming to be representatives of the IRA sings the song "The Boys of the Old Brigade." The song is told from the perspective of an elderly veteran of the Irish war of independence which had only began in January of 1919 which had happened only 3 years before. The song was written by Paddy McGuigan of the band Barleycorn in the 1970's.
Episode #1.4 - S1-E4
Factual error: When Freddy and Ada return to Birmingham from London they are seen on a boat called Kennet. This is a wide boat (i.e. almost twice the width of a 7 ft narrowboat) which could not have made its way from London to Birmingham in 1919/20 as all of the locks were narrow locks (7 ft) at that time.
Episode #1.4 - S1-E4
Factual error: In 1919 Chapman receives £200 from the Russian Embassy, but diplomatic relations were not established until 1924.
Factual error: Michael's impending 18th birthday is often mentioned as the time he becomes an adult and can make his own decisions. The age of majority in 1922 (and until 1970) was 21.
Factual error: Major Campbell heads the Irish branch of the secret service, but reports to Winston Churchill, the Colonial Secretary. The Colonial Office had nothing to do with Ireland, which at that time was part of the United Kingdom.
Episode #2.1 - S2-E1
Factual error: Season 2 covers 1921 to 1922. The car (YP8086) used in this episode was first registered 9th August 1926. (00:38:20 - 00:39:30)
Episode #2.1 - S2-E1
Factual error: Tommy refers to London at the south end of the Grand Union canal. However, the Grand Union in 1921/22 was what is now the Leicester branch. The Grand Union as it is known now was an amalgamation of 7 canals in 1929.
Episode #2.2 - S2-E2
Factual error: Tommy's service record quoted by Churchill says that he served throughout the war with the Warwickshire Yeomanry. But we already know that he was a tunneller on the Western Front. The Warwickshire Yeomanry was a cavalry regiment (which actually served in Egypt, Gallipoli and Palestine and finally as a machine-gun battalion on the Western Front at the very end of the war). All tunnellers served with the Royal Engineers.
Episode #2.2 - S2-E2
Factual error: Tommy tells Churchill that he served at Verdun and several of Churchill's assistants say that they did too. There were no British troops at Verdun. It was a battle between the French and the Germans.
Episode #2.5 - S2-E5
Factual error: The Metropolitan Police officers who arrest Arthur in Camden Town are wearing the spiked helmets of the Birmingham City Police, not the boss-topped helmets of the Metropolitan Police, which we do see at other times.
Episode #2.6 - S2-E6
Factual error: The field marshal is wearing a revolver to the Derby. British soldiers are only ever armed on duty, certainly not when attending social events. He also wears his Sam Browne outside his shoulder strap instead of beneath it; no officer would do this.
Episode #2.6 - S2-E6
Factual error: Tommy's warrant is signed by the 'Minister of the Empire'. There was no such post. The Colonial Secretary dealt with the British Empire.
