On 15 February 2003, mass marches were held to protest against a planned invasion of Iraq led by the United States. The invasion was part of an aggressive American military strategy against extremist Islamic terrorism following the 9/11 attacks in 2001. The US Government accused Iraq's leader, Saddam Hussein, of having links with al-Qaeda, the terrorist group that had carried out the 9/11 attacks. It was also claimed that Iraq possessed weapons of mass destruction.
The British Prime Minister, Tony Blair, strongly supported US President George W Bushand his plans for invasion. However, other countries such as Canada, France, Germany and Russia urged continued diplomacy. There was also no United Nations resolution to support the action.
Anti-war groups around the world organised a number of protests. The event on the 15 February 2003 was the largest and involved an unprecedented amount of international coordination.
Some of the largest protests took place in Europe. In Rome in Italy, around three million people were involved in a protest that entered the Guinness Book of Records. Thousands took part in a demonstration in the Turkish capital of Istanbul, despite local authorities having banned the protest. The events of 15 February were recorded as the largest protest of its type in human history.
In the UK, a huge protest was organised by the Stop the War Coalition (StWC) in partnership with the Campaign for Nuclear Disarmament (CND) and the Muslim Association of Britain. It attracted a diverse group of people, many of whom had never taken part in a protest before. London's march involved up to 2,000,000 people – a record for any British protest.
Despite the international protests and the lack of support from the UN, troops from the US, UK, Australia and Poland launched the invasion of Iraq on 20 March 2003.
Here are five photographs from the Stop the War protest in London, 15 February 2003.

Embankment,
London
15 February 2003
Protesters march along the Embankment in London as part of the anti-Iraq War march organised by the Stop the War Coalition, 15 February 2003. Embankment was one of two assembling points for the huge London march.

Whitehall,
London
15 February 2003
Protesters march along Whitehall in London, 15 February 2003.

Piccadilly Circus,
London
15 February 2003
Protesters march through Piccadilly Circus in London, 15 February 2003. After assembling at different points, the two mass groups of protesters converged at Piccadilly Circus.

Piccadilly,
London
15 February 2003
Anti-war protesters march along Piccadilly in London, 15 February 15, 2003.

Hyde Park,
London
15 February 2003
Anti-war protesters are seen massed in London's Hyde Park, where the 15 February 2003 demonstration culminated.