A 15ft dinosaur called “Chuck the Rex” was the centrepiece of a rally calling for the abolition of the monarchy ahead of the first anniversary of King Charles’s coronation. It will be a year since the king’s coronation on Monday, when gun salutes across the capital will commemorate his reign. About 100 people attended Sunday’s rally in Trafalgar Square in central London, which was organised by the campaign group Republic, alongside parallel events in Edinburgh and Cardiff. Protesters chanted “Abdicate, abdicate” in front of two large yellow banners that read “Abolish the monarchy” and “Change the country for good.” Graham Smith, the chief executive of Republic, said the group had brought the enormous puppet dinosaur to represent the anachronism of monarchy. “The fossilised remains should be in a museum where we can have a look at it and then we can enjoy actually living in a modern democracy,” he said. Smith and other Republic members were arrested last year for taking part in a pre-agreed protest on the day of the coronation. Smith was detained for 14 hours and launched a legal action against the Metropolitan police last year. He told the crowd the action was continuing. “We need to challenge the monarchy and the royals because it is a corrupt institution – they are a lazy people, they have not earned their position and they need to be kicked out,” he said. He continued: “We want a constitution and a system and a democracy that actually celebrates our very best principles and values. This won’t just be a matter of principle, it will change the way we govern ourselves and therefore change the society and the way that we see ourselves, not as subjects but as citizens.” Smith said the public was “forced to compromise our values and principles” and compared the scrutiny of politicians to that of the monarchy. “We criticise MPs for spending thousands of pounds on second homes … but we don’t criticise [Prince] William for spending £4.5m of our money on doing up not his second home, or his third home, but his fourth,” he said. Smith told the Guardian that the first year of Charles’s reign had seen a surge in interest in the idea of abolishing the monarchy. “We have grown enormously in the last 12 months, we’ve got more money, more members, more activists. There’s no way we could have organised this two years ago. Charles is not the queen [Elizabeth]. I mean, the queen was the monarchy for a lot of people.” While polling published on Sunday suggested an increase in support for King Charles, it also indicated a rise in people believing the UK should become a republic. Ipsos polling for the Mail on Sunday found 56% believe Charles is doing a good job as king, up from 49% last year. It also found that 28% of people supported Britain becoming a republic, compared to 22% four months before Queen Elizabeth’s death in 2023. The human rights campaigner Peter Tatchell, who has supported Republic for decades, was one of the speakers. He told the Guardian: “Monarchy symbolises elitism, privilege and deference. It’s totally incompatible with a modern 21st-century democracy. “The royals have between them 23 palaces and residences, 700 servants and a combined personal wealth of £2bn.” Tatchell said that support for the monarchy was “slipping”, pointing to the enthusiasm for republicanism among young people. The latest Ipsos polling found a third of young people said it “would be better” if the monarchy was abolished, compared with just one in six of older people. Shortly after the rally, the archbishop of Canterbury praised King Charles’s “sense of duty” as he returned to public events following his cancer diagnosis. In a statement released to coincide with the anniversary of the coronation, Justin Welby said it had been “the privilege of a lifetime” to anoint the king and queen in the ceremony. The king attended three events last week as he resumed royal engagements with the public. His first was meeting cancer specialists and patients receiving chemotherapy at University College hospital’s cancer centre in London. Reflecting on Charles’s handling of his ill health, Welby said: “The past year has presented the king with some great personal challenges. But I have been struck by his continued sense of duty, having recently returned to royal engagements following treatment. “His openness in sharing his condition has been characteristic of his willingness to help and support others.”