Thousands have descended upon Glasgow today as Yes Alliance campaigners gather to celebrate a remarkable political year at the Hope Over Fear rally.

Organisers expect the event, taking place in George Square and billed as a celebration of the rebirth of Scottish politics, to attract more than 14,000 people. It will feature live music acts, street entertainment and speakers from across the political spectrum.

Actor Martin Compston, one of several speakers scheduled to take to the stage, said: "Hope Over Fear is about keeping the momentum of the Yes campaign alive. We saw an unprecedented outburst of optimism as voters realised there was finally potential for change, and this event is to say not only are the 45% still here, but we're carrying the battle forward under a broad alliance of Scottish people.

"Walking out of the polling station on September 18 having voted for an independent Scotland was the proudest day of my life - an emotion only matched by the devastation of coming so close but losing. Today is about moving on from that, and ensuring we don't lose any of the ground gained over the last year."

Designed to reignite the extraordinary levels of public engagement of recent months and keep the fight for independence alive, the event takes its name from Tommy Sheridan's Hope Over Fear referendum speaking tour. But organisers stress they represent a range of groups from across the pro-independence movement, and that today's rally is not intended to promote any individual political agenda.

Anti-bedroom tax campaigner Gail Morrow, a member of the volunteer organising committee, said: "The intention from the outset has been that this is a festival of celebration for the entire Yes movement. The idea may have started with Tommy Sheridan's tour, but the people who come here are not doing it for any particular individual or political party. We've made a lot of effort to ensure the speakers taking to the stage are not exclusively politicians, but represent a wide range of perspectives and aspirations."

While controversial socialist campaigner Sheridan - who has been convicted of perjury - will speak at some point today, organisers say that Bob Thomson of Labour For Independence will also attend, while both the Greens and SNP have been invited to send representatives. In addition, the list of speakers is expected to include author Naomi Wolf and former UK ambassador Craig Murray, Loaves & Fishes foodbank chairman Denis Curran and actors Carmen Pieraccini and Keira Lucchesi.

For River City actor Lucchesi, the rally is no place for the specifics of policy, but rather a platform for celebrating a movement that has transformed political life in Scotland: "The campaign has taken the snobbery out of politics and put it back in the hands of people. Politics is life, and people believe that now in a way I don't think they could before."

However, Darren Carnegie, whose George Square food drives for his organisation Glasgow's Needy have captured the imagination and praise of pro-independence social media users in recent weeks, has accused Hope Over Fear organisers of attempting to hijack the sentiment of the Yes campaign for their own ends.

He said: "We were initially very excited about the rally, and approached the organisers to offer help and request that we continue to run our food drive alongside the event. But when we asked for a speaking slot to tell the crowd about our work they outright refused.

"We work in the same communities as Tommy Sheridan and he knows who we are. I can only think that this is an ego-driven decision based on fear we might steal his thunder, and I find it hugely disappointing that certain individuals are looking to use the movement to their own ends."

Hope Over Fear organisers have rejected that claim, saying the decision to hold the event on a Sunday was partially motivated by a desire not to disrupt Glasgow's Needy's regular Saturday food drives. They also point out that a food collection will be made on the day by the Loaves & Fishes organisation.

Morrow said: "We admire the work Glasgow's Needy does, but have partnered with Loaves & Fishes, a registered charity, to accept donations of food at the event. Put simply, there is no agenda here."

Questions, meanwhile, have been asked about fundraising efforts associated with the event. Local businesses have contributed in kind by providing the necessary safety barriers and first aid facilities for free, but organisers say they need to raise an additional £3000 to cover the extra cost of PA equipment hire and public liability insurance.

Rejecting suggestions of financial opportunism, organisers stress that while T-shirts will be sold for a minimum donation of £5 to help cover costs, entertainment like face-painting is free.

Fears have also been raised over social media threats from loyalists claiming they would disrupt the event. But Inspector Gavin Smith of Police Scotland said they have worked closely with Glasgow City Council and Hope Over Fear to ensure the rally is policed appropriately, while more than 100 stewards will ensure public safety.

Another organiser, Garry Maclachlan, said: "We do not expect any trouble but if any small-minded bigots do choose to try and disrupt proceedings Police Scotland have assured us they will be kept well clear of the area. We're here to celebrate ... and will treat any attempt at disruption or violence with the contempt it deserves."

For many of the thousands attending the rally today, however, this will be a celebration with a purpose - realigning the convergent forces that injected such energy into the independence movement and readying them for a fresh new campaign.