Arsenal's German World Cup winner Mesut Özil has become an increasingly political figure in recent years. After a meeting with Turkish President Recep Tayyip Erdogan eventually led to the end of his national team career, the midfielder has now drawn criticism in China for a social media post speaking out against what he sees as the persecution of the Uighur population in China.

One of the earliest examples of a sporting protest was in 1913, when the suffragette movement went mainstream thanks to the fatal protest of Emily Davison. On the day of the Derby horse race at Epsom, Davison entered the track and allowed herself to be hit by the king’s horse, Anmer. Her cause was to fight for the right of women to get the vote in Britain, which happened five years later.

Muhammad Ali refused to enlist to fight for the US in the Vietnam War in 1967. Already a boxing superstar, Ali based his decision on his beliefs as a Muslim and his opposition to the war. Ali was arrested, later found guilty of draft evasion, stripped of his titles, and had his fighting license suspended. Ali was out of the ring for three years until his conviction was overturned in 1971.

One of the most famous sporting protests was in 1968, when the Olympics in Mexico were rocked by Tommie Smith and John Carlos with their Black Power salutes following the final of the men's 200-meter sprint. Both athletes bowed their heads and raised black-gloved fists on the podium while the US national anthem played, a move that outraged millions of Americans.

US basketballer Mahmoud Abdul-Rauf rocked newspaper headlines in 1996 when he refused to stand for the national anthem before games, stating that the US flag was a symbol of oppression. He also said that standing would contradict his Islamic beliefs. The NBA suspended him and fined him more than $31,000 per missed game. He returned just days later after a compromise was reached with the league.

At the 1994 Commonwealth Games, Cathy Freeman celebrated her victories in the 200-meter and 400-meter sprints by carrying both Australian and Aboriginal flags during her victory laps to celebrate her indigenous heritage. She was rebuked by the organizers of the Games, but Freeman celebrated a gold medal at her home Olympics in Sydney in 2000 by carrying both flags again.

German-born Ghanian footballer Kevin-Prince Boateng took a stand against racist chanting in 2013 by walking off the field in a match against Italian fourth-tier team Pro Patria. The game was called off after 26 minutes when a section of Pro Patria supporters targeted the then-AC Milan midfielder, who reacted to the abuse by picking up the ball and kicking it at the crowd in the stand behind him.

The Black Lives Matter movement has been at the forefront of various protests and campaigns in the US recent years. One of the most prominent was in 2014 when LeBron James and fellow NBA players Kyrie Irving, Jarret Jack and Kevin Garnett wore “I can't breathe" shirts in reference to the last words of Eric Garner, an unarmed black man who died after a police officer had placed him in a chokehold.

Olympic silver medalist Feyisa Lilesa made a name for himself at the 2016 Olympics in Rio de Janeiro – but it wasn’t necessarily for his performance in the marathon. The runner crossed the line in second place with his arms above his head in solidarity with Oromo activists who were staging asylum protests in Ethiopia.

American footballer Colin Kaepernick knelt during the US anthem in 2016, sparking the now famous #TakeAKnee campaign in a protest against racial inequality and gun violence. President Donald Trump heavily criticized Kaepernick and the growing movement, which led to increasing anger from the players and many US citizens alike.

Gwen Berry and Race Imboden are the latest to show their anger over US social issues. A year before they compete in front of huge audiences at the Tokyo Olympic Games, the two protested against Donald Trump's policies — using stances made famous by Colin Kaepernick, and Tommie Smith and John Carlos decades before.

The Olympic Games were held in Ancient Greece from c. 776 BC-393 AD, until they were banned by Emperor Theodosius as a "pagan cult." French academic Pierre de Coubertin initiated their revival in Athens from April 6-15, 1896. Those Games were opened by Greece's King George. The Olympic Hymn, composed by Spyridon Samaras with lyrics by Greek poet Kostis Palamas, was performed for the first time.

Less than two years after the end of World War I, the Olympics were held in Antwerp. The Olympic flag, designed in 1913, was flown for the first time. The six colors on the flag - the white background plus blue, yellow, black, green and red rings - contain the colors of all other national flags. The athletes' Olympic oath (pictured) was also introduced as a commitment to fair and clean sport.

By the 1928 Summer Games in Amsterdam, much of the present-day protocol had been established. It was the first time the Greek national team entered the stadium first during the parade of athletes. Participating countries follow in alphabetical order according to a language chosen by the host country (usually its main language). Athletes from the host country march in last.

For the first time in 1936, a torch was relayed from Olympia, where the Olympic flame was lit, to Berlin - a tradition that has since become inseparable with the Games. The idea, said leading sports historian Manfred Lämmer, stemmed from Jewish archaeologist Alfred Schiff. Some 3,000 athletes participated in the relay and track star Fritz Schilgen (pictured) carried the torch into the stadium.

As Nazi flags were raised in Berlin for the Games, a much less foreboding flag incident occurred. When the teams from Liechtenstein and Haiti met at the opening, they were shocked to discover that their flags were identical. Liechtenstein responded by adding an emblem to theirs.

Yoshinori Sakai - also known as the Hiroshima Baby - was born on August 6, 1945, the same day the United States dropped an atomic bomb on Hiroshima. He was just 19 when he carried the Olympic torch into the stadium in Tokyo, setting a symbol for world peace and creating an unforgettable Olympic moment. The 1964 Games were the first to be held in Asia.

The Olympic Games are inseparable from the political climate. Dick Palmer, secretary of Britain's Olympic team (front right), is carrying the Olympic banner to represent the absent British Olympic Association in protest during the opening ceremony in Moscow. Japan and West Germany were among those that joined the US-led boycott and didn't attend to protest the 1979 Soviet invasion of Afghanistan.

In a spectacular display of sportsmanship, Catalonian Paralympic archer Antonio Rebollo didn't run the Olympic torch up to light the flame, but shot it with his bow and arrow at the opening of the 1992 Games in Barcelona. Apparently, he was instructed to shoot just above the cauldron, while an Olympic official lit the actual flame in a perfectly choreographed maneuver.

If the flame lighting in Barcelona was impressive, four years later in Atlanta, it was tear-jerking. Boxer Muhammad Ali was a controversial figure in the US after going to court for refusing to serve in the Vietnam War, but was also a hero for his athletic performance and commitment to his Muslim beliefs. While lighting the flame in 1996, he was visibly shaking due to Parkinson's disease.

In recent years, the artistic element of the otherwise strict protocol of the opening ceremony has taken on greater significance, though the motto of peace remains consistent. In 2004 in Athens - the birthplace of the Games - eccentric Icelandic singer Bjork performed her song "Oceana" and donned a dress that slowly unfurled over the athletes' heads to reveal a 10,000-square-foot world map.

Beijing pulled out all the stops in 2008 for an opening ceremony said to cost $100 million. (London in 2012 cost just $40 million.) Exactly 2,008 percussionists rigged with glowing sticks performed on fou drums, ancient Chinese percussion instruments. The thundering performance and show of unity was a highlight of the three-hour-long opening ceremony, which incorporated over 14,000 performers.

In London in 2012, Queen Elizabeth became the first head of state to have officially opened two Olympic Games. And she did so in style - with a stunt double "parachuting" into the opening ceremony. She opened her first Games as Queen of Canada in Montreal in 1976. In her speech, she declared per protocol: "I declare open the Olympic Games of 2012, celebrating the XXX Olympiad of the modern era."