Negar Mohseni clutched a red carnation and waited patiently under cold, drizzly skies as the queue slowly snaked its way towards the grave of Rosa Luxemburg. “I simply want to pay my respects,” said the 54-year-old Iranian. “Besides, she gives me the strength and motivation to continue to believe in the fight for social justice.”

A thick carpet of red blooms smothered the grave of the early 20th-century revolutionary leader and that of her fellow leftist agitator Karl Liebknecht at the Friedrichsfelde central cemetery in eastern Berlin. Both were murdered at the age of 47 on 15 January 100 years ago. Someone had left a note in a shaky hand that read “Peace, bread, roses, freedom”. People wiped away tears as they laid their flowers.

Facebook Twitter Pinterest Demontrators march behind banners to Friedrichsfelde cemetery on Sunday. Photograph: Michele Tantussi/Getty Images

The anniversary of the state-sanctioned murders of the founders of the Communist party of Germany (KPD) brought an estimated 20,000 people on to the streets of Berlin at the weekend for a march that marked the high point of a series of commemorative events, including theatre performances, readings and new biographies.

Although Liebknecht is held in high regard, it is Luxemburg who has been stealing the limelight. Not least, according to Mark Jones – assistant professor at University College Dublin and a leading expert on the German revolution of 1918-19 that culminated in the murders – because “she was a high achiever who rose in the very male-dominated world of Social Democratic politics”.

Facebook Twitter Pinterest Kit Aastrup, a retired social worker from Denmark: ‘History might well have taken a different turn had Rosa been able to fulfil her wishes.’ Photograph: Kate Connolly/The Guardian

She was considered a great orator and a prolific writer, cherished today by her leftwing supporters due to her opposition to the first world war and her fight for the rights of the working class, as well as the fact that her early death meant her reputation was not blemished by later disillusionments with the communist dream. Her name retains its popularity as a choice for her supporters’ female offspring.

Luxemburg’s slogans, along with portraits of her and Liebknecht, were held high on the red banners clutched by people as they made their way along the former Stalin Allee in eastern Berlin on Sunday, with hearty renditions of the Internationale and other revolutionary songs blaring out of portable speakers.

“Of course, the brutal and sudden end to her story raises the question of what would have happened if she had survived,” said Jones. “At its most advanced and powerful, the Rosa Luxemburg myth claims that had she lived, National Socialism may have never taken control of Germany.”

That was a view held by many at the demonstration. “I do believe the Nazis might not have come to power and history might well have taken a different turn had Rosa been able to fulfil her wishes,” said Kit Aastrup, a retired social worker who had taken a bus from Aarhus in Denmark to join the march. She wore a Russian ushanka ear-flap hat, embossed with a hammer and sickle.

A group calling themselves the “Yellow Vests”, a nod to France’s gilet jaunes movement, held a banner across the width of the street that read: “Remembering Karl and Rosa in 2019 means showing solidarity with the ‘yellow vests’.”

Facebook Twitter Pinterest Flowers on a memorial to Rosa Luxemburg at the Tiergarten park near the river Landwehrkanalin in Berlin. Photograph: Clemens Bilan/EPA

On the sidelines, a team from the British communist newspaper Morning Star was doing a roaring trade. “Red Rosa, the communist eagle,” ran the headline on its inside feature story on Luxemburg, referring to the affectionate title Lenin gave to the German communist. The article concludes: “Even after 100 years [her] memory still soars like an eagle to inspire revolutionary socialists all over the world.”

The Luxemburg tour

Uwe Hiksch, a member of the opposition Die Linke, or Left party, which sees itself as the natural inheritor of Luxemburg’s legacy, guides tourists around the Berlin landmarks connected to the murders. A recent tour took in the site of Eden, the hotel where Luxemburg and Liebknecht were brought by demobilised former soldiers, known as Freikorps to be beaten and shot. It continues to the location where Luxemburg’s body was thrown into the canal, and, a few hundred metres away, the Neuen See lake where Liebknecht was shot and killed.

When the Freikorps came to arrest her, Luxemburg was reading Goethe’s Faust. “She thought she was going to be taken to prison, she had no idea she was going to be murdered, so she brought a suitcase of books with her,” Hiksch said.

Facebook Twitter Pinterest Rosa Luxemburg. Photograph: Alamy

Far from uniting Germany’s left, the murders created a deep divide, still felt keenly today in the animosities that exist between the Social Democratic party (SPD), the junior coalition partner to Angela Merkel’s centre-right Christian Democrats, and Die Linke, successors to the communist party that ruled East Germany.

Recently, Andrea Nahles became the first leader of the SPD to come close to admitting her party’s role in the revolutionaries’ deaths, amid evidence that Gustav Noske, the minister of defence in the SPD-led fledgling Weimar government at the time, effectively signed off on the murders in an effort to crush the far left.

“It is probable that Gustav Noske had a hand in the murders of Rosa Luxemburg and Karl Liebknecht,” she told the party faithful in November at an event to discuss the 1919 revolt.

Noske was later involved in the farcical trials that followed the murders and that led to the acquittal of all but two of the suspects, who received paltry sentences.

“The SPD has a very difficult relationship with the 1918-19 revolution,” said Jones. “While various party historians openly admit the SPD’s role in the events, others still want to defend it.”

Facebook Twitter Pinterest Karl Liebknecht speaking at a peace rally in Berlin. Photograph: ullstein bild Dtl./ullstein bild via Getty Images

Even now, he said, Die Linke supporters argued that just as the SPD betrayed the working class then, so it continued to do with its labour reforms, seen as punishing the working class.

The London writer David Fernbach was among those who came to Berlin to pay tribute to Luxemburg and Liebknecht. His grandfather, Wolfgang, was a member of the Spartacus League, the Marxist revolutionary movement founded by Luxemburg and Liebknecht in reaction to the SPD’s support for the first world war. Wolfgang was murdered by government troops on 11 January 1919, when he was 30.

“Luxemburg made a huge contribution to the positive sides of German socialism at a time when it was free from the dogmatisms that were to follow, which is why I think she remains something of an untainted socialist icon today,” Fernbach said.