The men's 400 metres at the 2004 Summer Olympics as part of the athletics program were held at the Athens Olympic Stadium from August 20 to 23. Sixty-two athletes from 48 nations competed. The event was won by Jeremy Wariner of the United States, the sixth in what would ultimately be 7 consecutive American victories stretching from 1984 to 2008 and the 18th overall title in the event by the United States. The United States swept the podium for the 4th time in the event.
The women's 400 metres at the 2004 Summer Olympics as part of the athletics program were held at the Athens Olympic Stadium from August 21 to 24. The winning margin was 0.14 seconds.
Christine Ijeoma Ohuruogu, MBE is a British former track and field athlete who specialised in the 400 metres, the event for which she is an Olympic, World and Commonwealth champion. The Olympic champion in 2008, and silver medalist in 2012, she is a double World Champion, having won the 400 m at the 2007 and 2013 World Championships. She has also won six World championship medals in the women's 4 × 400 m relay as part of the Great Britain and Northern Ireland team and bronze Olympic medals in the women's 4 × 400 m relay at the 2008 Beijing Games and the 2016 Rio Games, her final Olympics. Ohuruogu shares with Merlene Ottey and Usain Bolt the record for medalling in most successive global championships – 9 – between the 2005 World Championships in Athletics and the 2016 Summer Olympics.
The 14th IAAF World Championships in Athletics was an international athletics competition held in Moscow, Russia, from 10 to 18 August 2013. Initially, Russia won the most gold medals to top the table for the first time since 2001. It was also the first time ever the host nation took the top of the medal table. However, following the disqualification of Russian sprinter Antonina Krivoshapka for doping and after the redistribution of medals in the Women's 4 × 400 metres relay, the United States moved to the top of the medal table with eight golds. In the overall medal count, the United States won 26 medals in total, followed by Kenya with 12. With 1,784 athletes from 203 countries it was the biggest single sports event of the year. The number of spectators for the evening sessions was 268,548 surpassing Daegu 2011.
Catherine Ann Murphy is a Welsh former athlete who competed mainly in the 200 metres and 400 metres. She finished fourth in the 4 × 400 metres relay at the 2004 Athens Olympics, fourth in the 400 metres at the 2003 World Indoor Championships, and won a bronze medal in the 4 × 400 metres relay at the 2005 European Indoor Championships.
Amantle Montsho is a female sprinter from Botswana who specializes in the 400 metres. She represented her country at the 2004 and 2008 Summer Olympics, reaching the final at the latter edition. She was the first woman to represent Botswana at the Olympics. She has also competed at the World Championships in Athletics and the IAAF World Indoor Championships, and is the former World Champion over the 400m, winning in a personal best time of 49.56 in Daegu.
The Women's 400 metres at the 2008 Summer Olympics took place on 16–19 August at the Beijing National Stadium. The winning margin was 0.07 seconds.
Natasha Monique Hastings is an American 400 meter track and field sprinter.
The women's 400 metres at the 2009 World Championships in Athletics was held at the Olympic Stadium on 15, 16 and 18 August. The world-leader prior to the competition, Sanya Richards, was regarded as the favourite in the event, although her previous failure to convert circuit dominance to major championship success raised some doubts. Reigning Olympic and world champion Christine Ohuruogu entered the championships as only the 25th fastest in the world that year, although a low-key run up also preceded her previous victories. Jamaicans Shericka Williams and Novlene Williams-Mills were predicted as possible medallists, while Russian Antonina Krivoshapka held the second fastest time in the world prior to the tournament.
The women's 400 metres at the 2005 World Championships in Athletics was held on August 7, 8 and 10 at the Helsinki Olympic Stadium.
The women's 400 metres competition at the 2012 Summer Olympics took place between 3–5 August at the Olympic Stadium.
Botswana competed at the 2012 Summer Olympics in London, United Kingdom, from 27 July to 12 August 2012. This was the nation's ninth appearance at the Olympics.
The Women's 400 metres at the 2011 World Championships in Athletics was held at the Daegu Stadium on August 27, 28 and 29.
Regina George Grause is an American-born Nigerian sprinter who specializes in the 400 metres. She represented Nigeria at the 2012 Summer Olympics and was the silver medallist at the African Championships in 2012.
Carline Muir is a Canadian sprinter, who specialized in the 400 metres. She won the bronze medal for the 400 metres, and ultimately, led her national team to claim the sprint relay title at the 2009 Summer Universiade in Belgrade, Serbia. She is also a three-time junior national champion, a two-time silver medalist at the Canadian Track and Field Championships.
The women's 4 × 400 metres relay at the 2013 World Championships in Athletics was held at the Luzhniki Stadium on 16–17 August.
The women's 4 × 400 metres relay at the 2014 IAAF World Indoor Championships took place on 8–9 March 2014. The gold medal was won by the United States, with Jamaica and Great Britain taking the silver and bronze, respectively.
The women's 400 metres event at the 2016 Summer Olympics took place between 13–15 August at the Olympic Stadium.
The women's 400 metres at the 2015 World Championships in Athletics was held at the Beijing National Stadium on 24, 25 and 27 August. Christine Ohuruogu of Great Britain entered the competition as the defending champion.
The women's 4 × 400 metres relay at the 2015 World Championships in Athletics was held at the Beijing National Stadium on 29 and 30 August.
