On 15 February 2003, a coordinated day of protests was held across the world in which people in more than 600 cities expressed opposition to the imminent Iraq War. It was part of a series of protests and political events that had begun in 2002 and continued as the invasion, war, and occupation took place. The day was described by social movement researchers as "the largest protest event in human history".
According to BBC News, between six and ten million people took part in protests in up to sixty countries over the weekend of 15 and 16 February.
The largest protests took place in Europe. The one in Rome involved around three million people, and is listed in the 2004 Guinness Book of World Records as the largest anti-war rally in history.