Nazi dictator Adolf Hitler greets supporters at a May Day gathering in the Olympic Stadium, Berlin. (Photo by Keystone). 1st May 1938

George Lincoln Rockwell (US Nazi Party, 1966). “George Lincoln Rockwell (March 9, 1918 – August 25, 1967) was the founder of the American Nazi Party. Rockwell was a major figure in the neo-Nazi movement in the United States, and his beliefs and writings have continued to be influential among white nationalists and neo-Nazis”.

Members of the federal police carry a Nazi statue at the Interpol headquarters in Buenos Aires, Argentina, Friday, June 16, 2017. In a hidden room in a house near Argentina's capital, police discovered on June 8th the biggest collection of Nazi artifacts in the country's history. Authorities say they suspect they are originals that belonged to high-ranking Nazis in Germany during World War II. (Photo by Natacha Pisarenko/AP Photo)

A protester dressed as a clown holds an umbrella over a Swiss police officer on a motorbike during a May Day demonstration in Zurich, Switzerland on May 1, 2017. (Photo by Arnd Wiegmann/Reuters)

A reveller walks through the streets in the early hours during traditional May Day celebrations in Oxford, Britain, May 1, 2015. (Photo by Dylan Martinez/Reuters)

Students from the University of St Andrews jump into The North Sea, as a good luck tradition before exams start on the East Sands in St Andrews, Fife, Scotland on May 1, 2018. (Photo by Derek Allan/Alamy Live News)

A demonstrator is detained during May Day rallies in Santiago May 1, 2013. (Photo by Ivan Alvarado/Reuters)

People walk past the Sleepwalker, a sculpture along the High Line in New York, US on May 10, 2016. The hyperrealistic work by Brooklyn artist Tony Matelli is part of the linear park’s Wanderlust exhibition. (Photo by Xinhua/Barcroft Images)