Captain George Mainwaring () is a fictional Home Guard captain, first portrayed by Arthur Lowe in the BBC television sitcom Dad's Army. In the 2016 film he is played by Toby Jones and in the 2019 remake of three missing episodes he is played by Kevin McNally. Mainwaring is the bank manager and Home Guard platoon commander, in the fictional seaside town of Walmington-on-Sea during the Second World War.

He is considered a classic British comic character owing to the continuing currency of Dad's Army via regular repeats and Lowe's portrayal. Many of his quotes, such as, "You stupid boy!", are engrained in British popular culture. In a 2001 Channel 4 poll Captain Mainwaring was ranked 21st in its list of the 100 Greatest TV Characters.

Personality Mainwaring was born in 1885 to Edmund Mainwaring and is a pompous, blustering figure with an overdeveloped sense of his importance, fuelled by his social status in Walmington-on-Sea as the bank manager and his status as captain and commander of the local Home Guard volunteer unit. He became leader of the unit by saying that he had served as a captain in the first world war, despite serving "somewhere in the Orkneys" and only being deployed to France in 1919, the year after the armistice was signed. He was later officially designated as the captain by the GHQ, in the episode "Room at the Bottom", after a brief reduction in rank. Despite his claim to be the son of a master tailor, it is revealed that his father was a poor draper and a heavy drinker, as is his profligate brother, Barry, who is a travelling salesman specialising in novelty toys. However, Mainwaring does have many redeeming qualities: he is essentially brave, loyal and industrious, generally kind-hearted beneath the bluster, and unfailingly patriotic.

Mainwaring believes in following rules and orders, sometimes to a ludicrous degree, and is class-conscious and a snob. Being educated at the local grammar school, as a scholarship student, he considers himself middle class and looks down on anyone he considers beneath him, which may be because he struggled to rise above his working class background. He claims to be the son of a successful tailor in Eastbourne, but Lance Corporal Jones reveals that Mainwaring's father was actually a poor draper who sold badly made workmen's trousers, and Barry Mainwaring confirms this. "If I had a title I'd be on the board of directors at the bank!" Mainwaring shouts at Sergeant Wilson when the latter gains a title in the episode "The Honourable Man". Despite his arrogance being encouraged by his status as the bank manager (having started as a clerk and working his way up to assistant chief clerk, chief clerk and eventually manager), Mainwaring reveals in the same episode that he considers it a mere "tinpot branch" and his career is at a seemingly permanent standstill, as revealed in "A. Wilson (Manager)?": whenever he applies for promotions, he is always turned down due to his unimpressive background. Mainwaring's pomposity and snobbery work against him, as he is frequently dependent on those in the Home Guard that he considers beneath him, such as Sergeant Wilson, his chief clerk at the bank with whom he shares an antagonistic friendship, and Private Walker, a black marketeer who interrupts Mainwaring's lectures with a quip or a sly revelation that Mainwaring is benefitting from underhand deals, despite his vocal disapproval of Walker's dubious business practices. Mainwaring is particularly envious of Wilson, who is more relaxed and charming and possesses combat experience that Mainwaring does not, and takes every opportunity to remind his sergeant who is the senior.

As a bank manager, he is efficient, if ruthless and stingy; as a military commander he can at first glance be seen as barely competent, such as being confused by the 24-hour clock, and his plans often result in chaos. Mainwaring nonetheless managed to pull a group of local shopkeepers "up by their bootstraps" to become some kind of fighting unit.

Mainwaring has no combat experience, which causes tension with the other members of the Home Guard, particularly Wilson, who was a captain in the Royal Artillery (Mons, Gallipoli, and Passchendaele) during the First World War. Mainwaring did, however, serve in the Army of Occupation in France, "during the whole of 1919 – somebody had to clear up the mess."Webber, Perry, Croft p. 132 He volunteered to enlist in 1914 but was rejected with poor eyesight (during the Second World War, John Le Mesurier, who played Wilson, had been a captain while Arthur Lowe was a sergeant major. Lowe tried to enlist in the Merchant Navy prior to the Second World War but was also rejected with poor eyesight).

Despite his shortcomings as a leader, Mainwaring considers himself an excellent military tactician. His height and background are frequently mocked as indicating a Napoleon complex and his nemesis, ARP Warden Hodges, often refers to him as "Napoleon". In one episode, "A Soldier's Farewell", Mainwaring dreams he is Napoleon Bonaparte and is thwarted at the Battle of Waterloo by a Duke of Wellington resembling Wilson.Webber, Perry, Croft p. 198 His pomposity and conviction of his prowess mean that Mainwaring yearns to be in control of any situation and he behaves in an arrogant manner; for instance in the first episode he organised the Home Guard unit and appointed himself commanding officer despite his lack of experience and qualifications (and had to wait until the episode "Room at the Bottom" before he received his commission).Webber, Perry, Croft p. 182

Mainwaring's patriotism can lead to xenophobia (he is not keen on the French, because they are "emotional" and "smell of garlic"; the Russians, because of their former alliance with Germany and their communism; the Americans, because of their late entry into the war and the fact that many of them have German names; the Italians, because of their opera and being the enemy; and the Germans, for obvious reasons). Mainwaring often refers to Hitler and the Germans as if he is leading his own personal war, insisting that "In fact I do wish he'd have a go – I'm spoiling for a fight" in "Asleep in the Deep", regarding his desire in an air raid to get out of a bunker and face the attacking Germans (who are in planes and beyond his reach). Mainwaring's position as captain of the Home Guard is a great source of pride and he dislikes being reminded that he is merely a volunteer, part-time soldier. In particular, in the episode "My British Buddy", he is offended when Wilson tells an American colonel that the Home Guard are not "real soldiers". Mainwaring's patriotism and eagerness to see combat tend to make him overconfident, and "I don't want to hear any of that sort of talk, Wilson" is a common response when Wilson points out problems. Mainwaring sees all regular British servicemen ("Our Boys") as exceptionally brave and resourceful, while seeing the Germans as inept and cowardly.

Mainwaring's character flaws, however, are presented in a comical rather than a spiteful manner and there is often a sympathetic subtext to his own personal neuroses; it is apparent several times that he devotes his energies to his Home Guard unit for a sense of comradeship and purpose lacking in other parts of his life, such as his career and marriage. On one occasion when his men spurned a parade to play darts against the ARP he expressed bewilderment, saying coming to the platoon is "the highlight of my day". It is frequently implied that he is trapped in a loveless and unhappy marriage to Elizabeth, his unseen wife, who is domineering, neurotic and withholding of affection. For example, in "If the Cap Fits..." Mainwaring reveals he learned to play the bagpipes on his honeymoon in Scotland because "there was nothing else to do". Mainwaring lives with his wife at 23 Lime Crescent, Walmington-on-Sea. In the episode, "My Brother and I", Mainwaring admits to Wilson that he had a lonely childhood and was devoted to his schoolwork, whereas his brother, Barry, always had friends. It is revealed in "Absent Friends" that Captain Mainwaring and his wife have a pet cat called Empress. In "The King was in his Counting House", it is mentioned that Captain Mainwaring and his wife have three goldfish. In "The Royal Train", Mainwaring reveals his desire to drive a train ever since he was a child, and that wish comes true.

Mainwaring has several redeeming qualities, including a deep concern for the welfare of the men under his command. His courage cannot be denied: he is willing to endanger himself for his country and platoon and to take the risks that he orders his men to undertake. In one episode, "The Battle of Godfrey's Cottage", the platoon thinks the Germans have invaded and Mainwaring, with his men, fights what they think is the German army but turns out to be other members of the platoon. He also clears bricks from a bombed-out corridor which could have fallen at any moment. Mainwaring insists that he works in the most dangerous position even though in drawing lots he had picked the safest ("Asleep in the Deep").

He also places the safety of his country above his own interests. In "Command Decision", Mainwaring is prepared to relinquish control so that the platoon could gain rifles, arguing that the defence of the country is more important than his ego.Webber, Perry, Croft p. 48 In addition he is prepared to "march in the ranks as Private Mainwaring" when he is briefly decommissioned as he had never actually been made an officer, implying that he was merely overzealous rather than a control freak.

He hates conscientious objectors; he sees them as abnormal as they do not want to fight for their country, as shown when he discovers Private Godfrey was a "conchie". However, when he learns Godfrey served at the Battle of the Somme as a medic and risked his own life (and received injuries) crawling into No Man's Land to save several men, earning him the Military Medal, he changes his opinion of Godfrey. Mainwaring says he cannot understand why Godfrey does not wear the medal.

Mainwaring is also capable of acting decisively and independently, although not always with the best of results. In "A Man of Action", Walmington is cut off when a bomb damages the railway and waterworks. Mainwaring imposes martial law and takes power from the mayor. Under his law people need permits to take a bath and looters will be shot. He changes position when this power is taken from him by an official from GHQ, describing such an act and the imposition of martial law as "monstrous".Webber, Perry, Croft p. 136

Mainwaring often claims to know something, only to be proven wrong almost immediately. The men under him, however, are mostly devoted to him. At heart, he is a kind-hearted man with a deep-rooted sense of duty.

Mainwaring has nearly had two affairs. One is in "Mum's Army" with a woman called Fiona Gray who joins the Home Guard when they recruit female soldiers. The pair start meeting in cafes all over the town. Gossip starts about them and Mrs Gray leaves by train. Another is with a bus conductor in "A Soldier's Farewell" whom Mainwaring compliments and defends when she is being flirted at. At the end of the episode, when Mainwaring dreams he is Napoleon, he dreams that the bus conductor is Marie Walewska (Napoleon's mistress). In "War Dance", Mainwaring claims to have been very vexed at Mrs Mainwaring and gave her a "good dressing down" when she burnt some sausage rolls. He turns and it is revealed he has a black eye. Mainwaring claims he did it on the wardrobe door, but it was obviously done in a domestic dispute. Walker later jokes, asking if Mrs Mainwaring has a rolling pin.