Peter Larsen was born in Berlin and raised in London. He studied briefly at Oxford, dropping out at the age of 17. He moved to Australia where he enlisted in the Royal Australian Air Corps. After six years, he left the RAAC and travelled through India and Africa, taking photographs for the Associated Press along the way. In 1960, Mr Larsen moved to New York, where he worked as a publicity photographer and studied photojournalism and design.
An avid traveller, in 1961 Mr Larsen embarked on an 18-country tour of Africa funded by UNICEF and Phoenix House. Photos from this trip appeared in numerous publications in the United States and Europe. In 1965, he began work on a freelance basis, travelling around the world for international organizations including the International Labour Organization, the United Nations, the Red Cross and UNICEF.
Mr Larsen's first assignment for WHO was in 1967. He travelled to South America and Europe and published photo stories on health topics including foot-and-mouth disease, public health, and malaria.