Pep Guardiola's current Manchester City side have ended hopes of replicating the Gunners' Premier League success after most recently falling to a 2-0 defeat at the hands of Chelsea – and though they won the league last season, were also unable to boast an unbeaten run after their streak was ended with the 4-3 loss to Liverpool in early January.
They did, however, go on to smash the record for the most points in a single campaign in the Premier League era with 100 points, and Manchester United have also won the title with more than the 90 the Gunners collected on their unbeaten run.
But neither, 14 years on, can say they have ever gone an entire season without losing a league game.
So just how did Arsenal do it? Goal have put together a complete guide to one of the most famous sides in English football history.
What are the Invincibles?
Arsenal usually lined up in a 4-4-2 formation, though it could also be labelled a 4-2-3-1 due to the way Dennis Bergkamp dropped into the 'No.10' position between midfield and attack.
The team is mostly remembered for its attacking genius. Thierry Henry was at the peak of his powers and finished second in the Ballon d'Or voting in 2003 and fourth in 2004, and while Bergkamp was nearing the end of his career he had not lost his brilliant movement or vision.
Left winger Robert Pires provided a secondary source of goals, netting 14 in the league, while Patrick Vieira was both the heart and brain of the team from central midfield. On the right, Freddie Ljungberg was a ferocious box-to-box player who raised his game for the big occasion.
What is not mentioned as often - particularly when comparing the Invincibles to today's Arsenal team - was that the Gunners were also outstanding defensively, conceding just 26 goals. Sol Campbell and Kolo Toure were a brilliant mix of athleticism and intelligence at centre-back, Jens Lehmann brought international class in goal and Ashley Cole and Lauren were a dynamic full-back pairing.
It was not just the quality of the personnel, however, but also the way they set up. Arsenal were more like Atletico Madrid than Barcelona, with both Gilberto Silva and Vieira tasked with shielding the defence and Cole and Lauren not allowing their desire to attack and overlap compromise their duties in their own half. Pires and Ljungberg did not hang around high up the field but were expected to track back and turn the ball over.
That commitment to defending made Arsenal an even better team going forward than their talent alone would suggest, because they were able to absorb pressure in their own half before launching lethal counter-attacks led by Henry.
Who was manager of the Invincibles?
After the victory over Leicester City that completed Arsenal's unbeaten season, the Guardian writer Kevin Mitchell labelled Arsene Wenger the most astute manager in the Premier League, and "probably all of football at the moment".
Wenger had not only revolutionised Arsenal but the entire division, introducing new training, fitness and dieting regimes that forced managers across the country to follow suit and demand greater professionalism and discipline from their players. Gone were the days of victories being celebrated with fatty food and several pints of beer.
The Frenchman's record of identifying players no one had heard of and moulding them into full internationals was also unmatched at that time. Toure was signed for £150,000 from an Ivorian club and converted from midfield and full-back into a central defender, while Ljungberg cost £3 million from Halmstads in Sweden.
Perhaps the most flattering compliment you can pay Wenger is that he was Sir Alex Ferguson's first true equal. The Arsenal boss has seen his star fall since, but in his first decade in north London he was a brilliant combination of tactical nous and ruthlessness, assembling teams that played scintillating football and were not intimidated by anyone.
Who were the key players of the Invincibles?
Thierry Henry can lay legitimate claim to being the greatest player of the Premier League era. He is not the only star in the conversation and some may argue that Alan Shearer and Ryan Giggs did it for longer, but only Cristiano Ronaldo has hit the heights of Arsenal's No.14 at his peak.
The Frenchman has been voted the Gunners' greatest ever, anyway, and netted a career-best 30 league goals during the unbeaten campaign. Quite simply, everything Henry did was fast; whether it be running, shooting or passing, it was as if he could do and see things twice as quickly as everyone else around him.
As was the case with about half of Arsenal's starting XI, Henry arrived at Arsenal with a much lesser profile than that which he left them with and had struggled on the left wing during a solitary season at Juventus. Wenger, who had coached him previously at Monaco, paid £11m to cut his stay in Italy short and made him a centre forward.
His partnership with Bergkamp was the perfect blend of speed, skill and intelligence. With the Dutchman's tendency to drop into the hole and Henry's fondness of pulling out on to the left flank, they were brilliant at finding space and left opposition centre-backs wondering whether to follow them and be dragged around the pitch or leave them unattended.
What results did the Invincibles achieve?
|Middlesbrough||0-4||Arsenal||Henry, Gilberto, Wiltord (2)||24/08/03|
|Arsenal||2-0||Aston Villa||Campbell, Henry||27/08/03|
|Manchester City||1-2||Arsenal||Wiltord, Ljungberg||31/08/03|
|Arsenal||3-2||Newcastle United||Henry (2), Gilberto||26/09/03|
|Liverpool||1-2||Arsenal||Hyypia (og), Pires||04/10/03|
|Leeds United||1-4||Arsenal||Henry (2), Pires, Gilberto||01/11/03|
|Arsenal||2-1||Tottenham Hotspur||Pires, Ljungberg||08/11/03|
|Birmingham City||0-3||Arsenal||Ljungberg, Bergkamp, Pires||22/11/03|
|Arsenal||3-0||Wolverhampton Wanderers||Craddock (og), Henry (2)||26/12/03|
|Arsenal||4-1||Middlesbrough||Henry, Queudrue (og), Pires, Ljungberg||10/01/04|
|Aston Villa||0-2||Arsenal||Henry (2)||18/01/04|
|Arsenal||2-1||Manchester City||Tarnat (og), Henry||01/02/04|
|Wolverhampton Wanderers||1-3||Arsenal||Bergkamp, Henry, Toure||07/02/04|
|Arsenal||2-1||Charlton Athletic||Pires, Henry||28/02/04|
|Blackburn Rovers||0-2||Arsenal||Henry, Pires||13/03/04|
|Arsenal||2-1||Bolton Wanderers||Pires, Bergkamp||20/03/04|
|Arsenal||4-2||Liverpool||Henry (3), Pires||09/04/04|
|Arsenal||5-0||Leeds United||Pires, Henry (4)||16/04/04|
|Tottenham Hotspur||2-2||Arsenal||Vieira, Pires||25/04/04|
|Arsenal||2-1||Leicester City||Henry, Vieira||15/05/04|
What was the Invincibles squad?
|5||DF||Martin Keown||3 (7)||0|
|7||MF||Robert Pires||33 (3)||14|
|8||MF||Fredrik Ljungberg||27 (3)||4|
|9||FW||Jose Antonio Reyes||7 (6)||2|
|10||FW||Dennis Bergkamp||21 (7)||4|
|11||FW||Sylvain Wiltord||8 (4)||3|
|15||MF||Ray Parlour||12 (10)||0|
|18||DF||Pascal Cygan||10 (8)||0|
|19||MF||Gilberto Silva||29 (3)||4|
|22||DF||Gael Clichy||7 (5)||0|
|25||FW||Nwankwo Kanu||3 (7)||1|
|28||DF||Kolo Toure||36 (1)||1|
|30||FW||Jeremie Aliadiere||3 (7)||0|
Includes all players to make at least one Premier League appearance.
What did the Premier League table look like for the Invincibles?