Every party has its foundational myth and the SPD claims to be the world's oldest democratic party. Certainly, it is Germany's.

The birth of the German Social Democratic Party belongs to a long-bygone era when workers with relatively few rights first began to rebel against the patriarchs of business who employed them. The fact that this group organized itself and became a politically potent force is, in large part, due to the work of a man named Ferdinand Lassalle.

On May 23, 1863, the well-to-do son of a merchant was the driving force behind the foundation of the General German Workers' Association (ADAV) in Leipzig. Now, 150 years later, Lassalle is considered the founder of what in the 19th century became known as the Social Democratic Party of Germany (SPD). One of the few parties that is actually older is the Republican Party of Abraham Lincoln in the United States, which was founded nine years earlier in 1854.

"The message of the SPD founders was: 'If you, workers, want to change your station, then you have to compel the state to make you equal and economically secure citizens of the state," recalls long-time top-ranking politician Erhard Eppler of the SPD party.

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Ferdinand Lassalle turned his frustrations into a political party

Through the help of workers' associations and the minimal benefits of the fledgling social democratic movement, destitute day laborers had their first opportunity to educate themselves professionally and politically. At that time, more than half of the citizens in the country were illiterate. Free elections and anonymous ballots had yet to come.

Franz Müntefering, a previous chairman of the SPD party, fondly remembers the story of ten men who were working professionally as "cigarette rollers."

"Nine were working, and the other sat in front and read from a book they'd all bought together, so that they could get something of a political and social education," he said.

Today, the SPD still considers Lassalle's promise — that social mobility was possible through education —one of its central aims..

Persecution, radicalization, resistance

"From the moment this association has even just 100,000 German workers," writes Lassalle in the first party pamphlet of his movement, "then it will have become a force that everyone will have to reckon with."

His case was proven in time. During the reign of the German empire between 1871 and 1918, what was once a workers' party quickly became a mass movement with upwards of one million members. In elections it obtained one-third of the popular vote.

Social Democrats were so popular that the chancellor of the newly-unified German empire, Otto von Bismarck, banned the party through a series of "Anti-Socialist Laws." For 12 years, trade-union-friendly proponents of social democracy were monitored, denounced and forced to emigrate.

"Ultimately the Anti-Socialist Laws even helped social democracy," Eppler says. "The SPD had its martyrs, and it was realized very quickly that we couldn't be suppressed, because the number of workers had just grown so quickly."

Scary time to be a socialist: a German home is searched in 1879 as part of the Anti-Socialist Laws

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Persecution led to radicalization within certain elements of the party. Larger numbers of social democrats began adopting the tenets of revolutionary Marxism, which foresaw the collapse of ruling capitalist structures and their replacement in a property-less and politically classless society.

By the end of World War I in November 1918, that philosophical crack had led inexorably toward a political schism, splitting the workers' movement into reformist and revolutionary factions.

When Germany's last imperial chancellor, Kaiser Wilhelm II, abdicated the throne on November 9, 1918, both branches of the social democratic movement called simultaneously for the founding of a new republic. From the chambers Berlin's Reichstag, or parliament, Philipp Scheidemann proclaimed a moderately democratic republic, while Karl Liebknecht called for a "socialist-communist" Germany.

But over the course of the 1920s and 30s, the term "social democracy" became associated with collapse. The Weimar Republic, founded and supported by a majority of moderate Social Democrats and representing the first phase of democracy on German soil, was politically instable during its short life between 1918 and 1933. Due to hyperinflation and mass unemployment, the country's economic condition appeared hopeless. Weak democratic institutions could no longer counteract the rise of National Socialists under Adolf Hitler.

Still, all 94 SPD parliamentarians voted against Hitler's "Enabling Act of 1933," a law that replaced democracy in Germany in favor of Hitler's despotism.

"One can take away our freedom and livelihoods - but not our honor," spoke then-SPD Chairman Otto Wels in the Berlin Reichstag.

Otto Wels rebuked Hitler at a time when many dissenting politicians remained silent and fearful

For Hans-Jochen Vogel, a long-time and high-ranking SPD politician, this final, unsuccessful appeal against the Nazi regime is to this day one of the greatest moments in German democracy.

"Every other party voted in favor [of Hitler's Enabling Act]," he said.

The SPD kneels

At the end of World War II in 1945, what remained of the SPD had become a leftist popular front whose chief preoccupation was with itself in the post-war years. As Germany's conservative political party enacted capitalist reforms and set the country on a path that would lead toward the "economic miracle," the SPD corrected and revamped its anti-capitalistic attitudes.

In the Godesberg Program of 1959, the party embraced the market economy - albeit one girded with strong social security mechanisms. For former SPD general-secretary Franz Müntefering, that document represented the symbolic re-birth of his party.

"That was the first time that everyone who was committed to the ideals of social democracy was invited to participate," he said.

In 1966, with the beginning of the grand coalition between the SPD and its traditional center-right rival, the Christian Democratic Union (CDU), a decade of post-war development shaped by the SPD had arrived. Where SPD politicians of various generations had previously anchored their policies on women's suffrage, eight-hour workdays and support for trade unions, in 1969, German Chancellor and SPD chairman Willy Brandt set his attention to peace and reconciliation with the socialist states of Eastern Europe. Brandt received the Nobel Peace Prize in 1971 for dropping to his knees at the Monument to the Ghetto Heroes in Warsaw, an act which, as performed by an active German Chancellor, became the symbolic apology to the Polish nation for the crimes of the Nazi dictatorship.

In kneeling, Brandt became a symbol of German remorse and the most recognizable SPD politician worldwide

"It was the instinct of a moment that moved him toward a gesture, through which a person who bore no personal guilt asked forgiveness for the guilt of his people," recalled Egon Bahr, the architect of Brandt's policies in Eastern Europe.

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Crisis and new beginnings

For Müntefering, cigarette rollers from a century ago continue to provide lessons for today

In the years before and after the peaceful unification of East and West Germany through the fall of the wall in 1989, the SPD again found itself on unsolid ground. Helmut Kohl of the CDU was considered the "chancellor of unification," a reputation that carried politicians of his center-right party to government seats for many years to come.

Read more: The SPD stronghold of Bergkamen

The SPD, meanwhile, remained an opposition party in Germany's parliament until 1998. It was only after the election victory of the SPD and Chancellor Gerhard Schröder in that year that the party found the courage to seek renewal. Schröder transformed the SPD, a former workers' party, into a party of the "new middle" so that it might find electability among white-collar workers, the self-employed and those of the now-shrinking working class. High unemployment and an economic recession, however, caused the Social Democrats to instead usher in a radical restructuring of the labor market and social system through a reform concept called "Agenda 2010."

The party's traditional voters - industrial workers and low-income earners - turned their backs on the SPD, a fact that, by the end Gerhard Schröder's chancellorship in 2005, led to an identity crisis within the party.

The party plummetted to well below 30 per cent on the national level and in most of the federal states. Any boost it received has so far been short-lived.