Max Pearson presents a collection of the week's Witness History interviews from the BBC World Service.

The expert guest is Dr Mirjam Brusius, a research fellow in colonial and global history at the German Historical Institute.

First, we hear about Martín Chambi - Peru's pioneering documentary photographer.

Then Amaize Ojeikere talks about his father, JD 'Okhai’ Ojeikere, who created an iconic collection revealing the elaborate ways African women styled their hair.

Plus, the story of Magnum Photos – the picture agency started up by World War Two photographers.

And, Vivian Maier, the nanny who - since her death - has been hailed as one of the best street photographers of the 20th century.

Finally, the mystery behind Lunch Atop a Skyscraper – the famous photograph showing 11 ironworkers eating lunch nearly 70 storeys high.

Contributors:

Roberto Chambi – grandson of photographer Martín Chambi Dr Mirjam Brusius - research fellow in colonial and global history at the German Historical Institute Amaize Ojeikere – son of photographer JD 'Okhai’ Ojeikere Christine Roussel – Rockefeller Center archivist Jinx Rodger - widow of George Rodger, one of the founders of Magnum Photos Inge Bondi - Magnum Photos employee

This programme has been updated since the original broadcast.

(Photo: Two books of photographs in the exhibition 'Martin Chambi and his contemporaries’. Credit: Getty Images)

Max Pearson presents a collection of the week's Witness History interviews from the BBC World Service. Our guest is Dr Elizabeth Abbott, writer, historian and author of the book, "Sugar: A Bittersweet History".

First, we confront the dark history of sugar.

We hear how a researcher in the 1990s uncovered the unethical aspects of Sweden’s Vipeholm experiments in the 1940 which led to new recommendations for children to eat sweets just once a week.

And, how Mexico, a country which had one of the highest rates of fizzy drink consumption in the world, approved a tax on sugary soft drinks in 2013.

Then an event which shaped the second half of the last century - On 14 May 1955, the leader of the Soviet Union and Heads of State from seven European countries met to sign the Warsaw Pact.

Plus, the story of how two rival electricity pioneers, Nikola Tesla and Thomas Edison brought electricity to the world.

Finally, we hear from Finnish singer Marion Rung on winning the 1980 Intervision Song Contest, the USSR’s answer to Eurovision.

Contributors:

Dr Elin Bommenel - academic Dr Simon Barquera - director of health and nutrition research at The Institute for Public Health of Mexico Dr Elizabeth Abbott - writer and historian Otto Grotewohl - German politician Mark Seifer - biographer of Nikola Tesla William Terbo - relative of Nikola Tesla Marion Rung - Finnish winner of Intervision song contest 1980

(Photo: sugar cubes and fizzy drinks, Credit: Anthony Devlin/Press Association)

Max Pearson presents a collection of the week's Witness History interviews from the BBC World Service. Our guest is Rubina Raja, professor of classical archaeology and art at Aarhus University in Denmark.

First, we go back to May 2015, when the ancient city of Palmyra in Syria was about to fall to Jihadist fighters and how of a group of men risked their lives to preserve the world-famous archaeology.

Plus, the entrepreneur and engineer Yoshitada Minami and his wife Fumiko Minami who came up with a way to liberate women from two to three hours of housework a day through the invention of the rice cooker in 1955.

Then the story of the sinking of the Lusitania, the British ocean liner sunk by a German submarine off the coast of Ireland during the First World War.

Also, celebrating 80 years since the end of the Second World War in Europe we dive into the BBC archives to listen to correspondents capturing the scenes of joy across London on VE day in 1945.

Finally, how in 2000, keen cricketer Paul Hawkins wanted to turn his passion into innovation when he created the technology we now known as ‘HawkEye’.

Contributors:

Khalil Hariri - archaeology expert who worked at Palmyra’s museum Rubina Raja - professor of classical archaeology and art at Aarhus University in Denmark Aiji Minami - son of Yoshitada and Fumiko Minami Margaret Hague Thomas – passenger on the Lusitania Leslie Morton – merchant seaman on the Lusitania Paul Hawkins – founder of ‘Hawkeye’

(Photo: Palmyra. Credit: PHAS / Universal Images Group via Getty Images)