Nelson's 'Victory' joins him in Trafalgar Square

It is Trafalgar Square, named after the naval battle of 1805, so it might seem fitting that the space on the square's celebrated empty fourth plinth should be occupied by a memorial of the battle – and, as of yesterday, so it is.

Nelson's Ship in a Bottle is a 1:30 scale replica of HMS Victory, the flagship of Admiral Horatio Nelson who at Trafalgar defeated the combined fleets of France and Spain in the greatest sea battle of the Napoleonic wars. It has been created by the leading Anglo-Nigerian artist Yinka Shonibare.

But inside its 4.7m by 2.8m bottle, is the model battleship, with its 37 large sails made of brightly patterned African fabric, a celebration of British historical power and victory? Or a subtle subversion of it?

Boris Johnson, the Mayor of London, made the point yesterday in welcoming the new artwork when he said: "The fourth plinth is about enigma and this will be a national conversation piece – people will ask what it says: is it pro-empire, is it anti-empire?"

He went on: "Yinka Shonibare's sculpture is the work of an artist at the top of his game. This colourful and quirky take on our seafaring heritage provides a vivid contrast that intensifies the historic surroundings of Trafalgar Square. As with the times, it's a vibrant coalition bringing together the traditional and the contemporary, showing London to be creative and forward looking."

Commissioned by the Mayor, and supported by Arts Council England with sponsorship from Guaranty Trust Bank of Nigeria and the Henry Moore Foundation, the artwork is the first commission on the fourth plinth to reflect specifically on the historical symbolism of Trafalgar Square, and links directly with Nelson's column. It is also the first commission by a black British artist.

"London is such a diverse community, and art is a fantastic way to engage everyone regardless of race, class or gender," Yinka Shonibare said. "It is particularly great that this piece is an expression of Nelson's legacy, a legacy which has contributed to the diversity of this city."

London-based Shonibare, who was born in Britain, moved to Nigeria aged three and studied art in the UK, is known for his works exploring colonialism and was made an MBE in 2004.