It is the eve of the First World War and Kahn's photographers are travelling from the West, where they capture the timeless values of traditional rural lives, to the East, where they witness the emerging force of nationalism – a force that would plunge Eastern Europe, and then the world, into war.

This episode details the origins of the project with fascinating background to the invention of the autochrome system, and introduces the archive's creator, Albert Kahn. It also tells the story of two incredible journeys undertaken in 1913: one by Auguste Léon to London and Cornwall, the other by the project's only female photographer, Marguerite Mespoulet, who travelled along the west coast of Ireland.

Men Of The World – the second of this fascinating, five-part series chronicling the adventures of Kahn's photographers as they journeyed around the globe – tells the story of Kahn and Dutertre's intrepid global odyssey: an adventure that would produce some of the earliest-known colour pictures taken in the US, Japan, China and Brazil.

Between 1914 and 1918, Kahn dispatched several members of his team to the battlefields, where they recorded in remarkably intimate detail the everyday lives of the French troops fighting at the front. In The Soldiers' Story, viewers see them cooking their meals and even laundering their uniforms behind the front lines at The Battle of Verdun. But they also see harrowing images of death and destruction in which whole towns are razed to the ground leaving a desolate, almost lunar, landscape. Viewers witness crude medical procedures at a field hospital, and see some remarkable early shots of the aeroplanes and heavy artillery which were beginning to appear on the battlefields.

In The Civilians' Story, viewers see harrowing images of the many French towns that were razed, their churches and civic buildings destroyed to leave a desolate, almost lunar landscape. The programme witnesses some of the individual acts of quiet heroism by the nurses and doctors who tended the wounded, and sees the relief and sheer joy of the Armistice Day celebrations.

When the Armistice was signed in November 1918, Kahn's team photographed the scenes of jubilation in Paris as they witnessed the negotiations at the Paris Peace Conference and recorded the horrifying aftermath of four years of war and the upheaval that followed war in the Rhineland and Turkey.

The First World War led to the disintegration of the Ottoman Empire and its former provinces came under the control of France and Britain. Though as the occupying troops arrived, the people of present-day Syria, Lebanon and Palestine were already entertaining hopes that they would be able to govern themselves. Albert Kahn's cameras were there to record the establishment of new nations.

Between 1914 and 1928, Kahn sent some of his most talented photographers to the Far East. In Cambodia, Vietnam and Japan, they produced a compelling photographic record of economic and cultural life, subsistence industries, and ceremonial practices, and produced a fascinating portrait of the life of a wealthy Maharajah in India during the British Raj.

The last programme in the series shows the films shot by Kahn's cameraman Lucien Le Saint who joined the French fishing fleets in Newfoundland, the film and colour autochromes shot by Frederic Gadmer who recorded Voodoo religious practices in Benin and the experimental colour films produced by Camille Sauvageot in 1928, depicting the lives of farmers, Gypsies and bullfighters in France.

Some of the most important of all the 72,000 colour images in Kahn's Archive were shot during three separate visits (in 1908, 1912 and 1926) to Japan. As an international financier, Kahn had established a network of contacts that included some of the most prominent members of Japan's business, banking and political elites. Consequently, Kahn's photographers were granted privileged access to places that would have otherwise been off limits - including some of the royal palaces, where they shot colour portraits of the princes and princesses from Japan's Imperial family. But some of their most fascinating images capture moments from the lives of ordinary Japanese people at work and play. This film showcases Kahn's treasury of films and autochromes of silk-farmers, Shinto monks, schoolchildren, porcelain merchants, Kabuki stars and geishas - pictures that were recorded at a time when this fascinating country was going through momentous changes.