Even as Paweł Adamowicz was lying in state at Gdańsk’s European Solidarity Centre, a museum, archive, and public space dedicated to the history and values of the independent trade union born in the city’s shipyards, its grief-stricken staff were preparing his entry into history.

The opening of the museum in 2014 was the realisation of a dream for Adamowicz, a Gdańsk native who had long sought to present his city to the world as a symbol of Europe’s hard-won freedom. In between shifts maintaining an overnight vigil by his coffin, researchers gathered materials with which to commemorate him.

“We are working, we are making films, we are writing texts, but still I don’t think we can accept that this situation is real,” said Anna Mydlarska, head of the museum’s documentary film section, ahead of Adamowicz’s funeral on Saturday. She had first met him during a student strike in the late 1980s. “I am working on all this material in which Paweł Adamowicz is alive, and I can’t fully accept and absorb the fact that he is now a part of history, a part of the past. People are so shaken, we feel orphaned.”

Gdańsk map Gdańsk map

Gdańsk remains in mourning for its mayor, who was stabbed on stage at a charity concert last Sunday evening and died the following day. On Saturday, the streets of its picturesque old town were filled for his funeral in the giant brick St Mary’s Basilica. Black-and-white photos of Adamowicz hung in shop windows as mourners carrying flags of Gdańsk and Pomerania watched the service on big screens outside.

The murder of Adamowicz, a staunch defender of minority rights at a time of rising levels of hate crime and an ardent liberal critic of the ruling conservative party’s anti-immigrant politics, has provoked an anguished and often ill-tempered national debate about hate speech and polarisation in Poland’s deeply divided society.

“I am convinced that Paweł would want me to say the following words,” Dominican priest and anti-communist activist Ludwik Wiśniewski declared in a powerful eulogy that drew applause from the congregation and the crowd outside. “We must end hate. We must end hate speech. We must end contempt. We must end baseless accusations against others.”

Paweł would want me to say, we must end hate. We must end hate speech Ludwik Wiśniewski, speaking at Adamowicz's funeral

But as the debate surrounding the circumstances of Adamowicz’s death continues, attention in Gdańsk is also turning to the life, legacy and personality of a native son who served as its mayor for more than 20 years, transcending many of Poland’s traditional political and cultural divisions.

“He had unbelievable warmth – you could see the sympathy in his eyes,” said Jerzy Limon, professor of English at the University of Gdańsk, and a friend. “His love of the city was so strong, he was not one of those politicians who could just go anywhere. Gdańsk was his beloved, and the city is his greatest monument.”

Adamowicz rose to prominence in 1988 as a law student at the University of Gdańsk, where he led a student strike in solidarity with workers striking in the city’s shipyard. “It was a period when people were tired of communism but they were also tired of fighting communism,” recalled Wojciech Szeląg, now a broadcaster, who participated in the strike. “It wasn’t a time of hope, it was a time you could paint only in grey. But I remember thinking that if people like Adamowicz were involved, it was worth it.”

“He stood out – not just physically, because he was very tall but because he wasn’t the slightest bit aggressive,” said Mydlarska. “He was always smiling and ready to joke. He spoke slowly. He liked to quote the motto of Gdańsk: Nec temere, nec timide, ‘neither rashly, nor timidly’ – he loved that motto. He was part of the Gdańsk tradition of courage without aggression.”

Facebook Twitter Pinterest Mayor Adamowicz speaking at the charity event on 13 January before he was stabbed. Photograph: Bartosz Bańka/Reuters

After the fall of communism, and still in his 20s, Adamowicz was elected to the city council in 1990, serving as head of the council from 1994 until his election as president of the city in 1998 at the age of 32.

Those who knew and worked with him say his worldview was profoundly shaped by the experiences of his parents, who moved to Gdańsk in the 1940s from Vilnius, now the capital of Lithuania, as part of a wave of Polish people expelled from territory seized by the Soviet Union in the aftermath of the second world war. As Adamowicz would later recount, they brought with them an outlook rooted in the multicultural traditions of Poland’s eastern borderlands, which fitted perfectly with Gdańsk’s own history as a coastal trading city.

“For most of its history, Gdańsk was a multinational city, a kind of united Europe in miniature, where different nationalities lived together in peace – a wonderful historical example of openness and understanding, a city prepared to accept immigrants,” said Limon, whose own family is also from Lithuania. “When people came from eastern Poland and settled here, they somehow incorporated Gdańsk’s history into their own. Paweł’s family was from the east, and he inherited this love of openness.”

Adamowicz worked closely with NGOs and civil society to establish mechanisms that would defend and uphold minority rights, with a particular focus on the integration of large numbers of migrants from the former Soviet Union, and his determination appeared to grow in the face of increasing anti-migrant sentiment associated with the rise to power of the Law and Justice party in 2015.

A committed Catholic with a background in conservative politics, he frequently defended his robust stance on minority rights in religious terms, incensing many on the Polish right, including elements of the Polish Catholic church. “In this festive season, I will try to explain to my compatriots in Gdańsk that the arrival of Christ was the very example of migration,” he told a meeting of the European Committee of the Regions in December 2016.

“It is very rare to challenge the church but it is even more rare to challenge the church on the basis of its own social teachings,” said Marta Abramowicz, an LGBT activist and co-founder of Poland’s Campaign Against Homophobia, who moved to Gdańsk from Warsaw in 2010. “He didn’t just support us, he supported us proudly and openly, he said that it was important that we were a part of Gdańsk.”

Facebook Twitter Pinterest Mourners watch the funeral in the nearby Basilica of St Mary. Photograph: Sean Gallup/Getty

“He was a religious conservative who was loved by the feminist movement – this is why he was extraordinary, and this is why we will miss him so much. We need politicians who say it’s not leftist or communist to believe in human rights, it is just normal,” said Marta Siciarek, director of Gdańsk’s Immigrant Support Centre, which was set up in 2012 with Adamowicz’s support.

“It wasn’t just talk, we had real challenges we needed to deal with. We had small children begging on the streets, and now the city is funding day care for them. But there is so much more we need to do, we still need him.”

At a time of acute partisan discord, the assassination of a man who so ostentatiously eschewed aggression while seeking to root progressive values in Poland’s patriotic traditions – as illustrated by the mournful Arabic prayers sung by a representative of Gdańsk’s Muslim community in St Mary’s Basilica during the funeral service – has only heightened people’s grief and confusion.

But in her eulogy, Adamowicz’s widow, Magdalena, reminded the congregation of her late husband’s last words. “This is a wonderful time to share what is good,” he had told the crowd gathered at the charity concert just before the attack. “You are all so lovely, Gdańsk is the most wonderful city in the world.”