Fifty-six years ago, they weren't even invited to be part of the newly created Bundesliga, and yet in the space of just over half a century Bayern Munich have emerged from relative obscurity to become the best-supported club in world football.
Bayern are by far and away the most successful club in Germany, with a staggering total of 29 league titles, 19 DFB Cups and five UEFA Champions League crowns, as well as a clutch of other domestic and continental trophies. But what makes them stand out from the other giants of the game - Real Madrid, Barcelona and Manchester United - is the sheer enormity of their fan base.
The Bavarian giants boast no fewer than 290,000 official club members, which puts them over 100,000 clear of fellow European heavyweights Benfica and Barca. The top five is completed by Bundesliga rivals Borussia Dortmund and Schalke, who both have just over 150,000 members.
So how did it all come about? Thanks to a flair for sniffing out talent, some smart decision-making at the top - and a healthy dose of good luck, as bundesliga.com explains...
Watch: Bayern Munich - all you need to know!
Second fiddle to 1860
Back in 1963, 1860 Munich, rather than Bayern, were the city's dominant side. Having just won the Oberliga South, 1860 were chosen along with four other teams from the division - including Eintracht Frankfurt and VfB Stuttgart - to become part of the newly founded Bundesliga, which brought together 16 clubs from the country's five regional leagues.
Bayern were outraged. After all, they had come third in the Oberliga South that year - above Frankfurt, Karlsruher and Stuttgart - but the DFB only wanted a single representative per city, and so champions 1860 got the nod. Bayern would have to wait until 1965/66 to win promotion to the top tier, although those extra few years in the Oberliga would turn out to be a major blessing in disguise.
With their finances in disarray, Bayern were forced to shed their expensive stars and go back to the drawing board, developing talented youngsters from the local region and their own youth system. Those players included the remarkable trio of Gerd Müller, Sepp Maier and in particular Franz Beckenbauer, who would have a profound impact on the club's development in the 1970s.
Der Kaiser's decision
The history of Bayern could have been very different were it not for an infamous youth tournament in 1959. Beckenbauer had grown up idolising Fritz Walter, Germany's 1954 FIFA World Cup-winning captain, and as a 14-year-old he was an aspiring centre-forward with SC 1906 Munich. The trouble was, SC 1906 had run into financial trouble and could no longer afford to run their youth teams - so Beckenbauer and his teammates decided to join the 1860 academy instead. After all, 1860 were his favourite club and it had always been his dream to play for them.
The Under-14 tournament in Neubiberg changed all that. Beckenbauer's SC 1906 team came up against 1860 in the final and things took an ugly turn, with the future Germany captain even coming to blows with the opposition centre-back. The incident changed his mind about going to 1860 and he ended up on the Bayern books instead. The rest, as they say, is history.
The golden generation
Bayern might never have become the global giants they are today without the pioneering successes of the 1970s. Beckenbauer emerged as the team's natural leader, trading his dreams of goalscoring glory to star as an elegant, ball-playing centre-back. Maier was a goalkeeper of outstanding ability and athleticism, while Müller's prodigious scoring records are unlikely to ever be broken.
Beckenbauer captained Bayern to three consecutive Bundesliga titles between 1972 and 1974, and enhanced his growing international reputation by helping Germany win the 1972 UEFA European Championship and the 1974 FIFA World Cup. Winner of the Ballon d'Or in 1972, he was honoured again in 1976 as Bayern extended their dominance to the continent, claiming three consecutive European Cups between 1974 and 1976.
Going global with his Hoeneß
While Beckenbauer laid the foundations for Bayern's future sporting success, it was another member of the all-conquering 1970s generation who continued to take the club forward on and off the pitch. Despite being seven years younger than 'Der Kaiser', Uli Hoeneß was forced to end his career four years earlier, aged just 27, due to a serious knee injury sustained in the 1975 European Cup final. Crucially, though, he stayed on at Bayern and became the Bundesliga's youngest ever general manager.
At the time, Bayern were in debt to the tune of around €3.5 million, while annual turnover was just over €6 million. By the time he left his post to become president 30 years later, Hoeneß had transformed the Bavarians into one of the world's richest clubs, with an annual turnover in excess of €300 million.
As well as ensuring that the club continued to enjoy domestic success - seven more league titles followed in the 1980s, another six in the 1990s and early 2000s - Hoeneß developed Bayern's merchandising and promotional activities, helping to add millions in revenue. He also brought in big-name coaches such as Jupp Heynckes, Giovanni Trapattoni and Ottmar Hitzfeld, and it was the latter who finally brought the Champions League back to Bavaria in 2001 after three heart-breaking final defeats (1982, 1987, 1999).
More than the sum of their 50+1 parts
One of the key factors behind Bayern's unrivalled popularity - aside from their on-field achievements - is the 50+1 rule that underpins German football, dictating that clubs must be majority owned and controlled by their members, rather than a single financial backer. While there are exceptions - Bayer Leverkusen, Wolfsburg, Hoffenheim and RB Leipzig - Bayern are certainly not one of them, as their incredible membership figures demonstrate.
Bayern hold their many fan clubs in great esteem, and regularly dispatch star players to spend time with supporters, especially during Oktoberfest and in the run-up to Christmas. As well as committing to various social and charitable initiatives, the club also has a long history of solidarity with other German clubs in financial difficulty, having lent a helping hand to their old rivals 1860, St Pauli, Hansa Rostock and even Dortmund down the years.
The club's policy of putting the fans first has also kept ticket prices down. Bayern may be one of the most successful football teams in the world, but it is still possible to get hold of a season ticket at the Allianz Arena for as little as €140, which works out to around €8 per game.
Watch: Take a look inside Bayern's space-age Allianz Arena
The future's bright, the future's red
Between their phenomenal recent success on the pitch and the club's robust financial situation, Bayern look certain to keep lighting up the domestic and European football scene for many years to come. The Bavarian giants have won the last five Bundesliga titles and are well on course to make it six, while Heynckes - who recently returned for his fourth stint in charge - famously guided them to a historic treble of Bundesliga, DFB Cup and Champions League in 2012/13.
Bayern are the sole owners of their ultra-modern, 75,000-seater Allianz Arena, which marked the club's arrival in the 21st century when it was inaugurated in 2005. Meanwhile, they recently announced a record turnover of €657.4 million for the 2017/18 season.
The club is also home to some of the biggest names in world football, which has contributed to the proliferation of its global fan base. Manuel Neuer is widely held to be the world's best goalkeeper, and is one of six World Cup winners in the current squad, along with fellow Germans Jerome Boateng, Mats Hummels and Thomas Müller, Spain's Javi Martinez and France's Corentin Tolisso.
David Alaba and Robert Lewandowski are also among the world's best in their positions, while exciting youngsters like Kingsley Coman, Serge Gnabry, Leon Goretzka, Joshua Kimmich, Niklas Süle and Alphonso Davies are proving on a weekly basis that the club's future is in very safe hands.
They're Germany's most successful club by a considerable margin, one of the best in Europe, and have consistently produced some of the finest footballers in every generation. Talented and ambitious on the pitch, generous yet disciplined off it, there are probably 290,000 reasons why Bayern Munich are the world's biggest and most popular sports club. Just ask their members.