Different Irish experiences of first World War shown through lives of four people

Long before his contemporary namesake earned his uncompromising reputation, the name of Michael O'Leary was synonymous with belligerence. Cork-born O'Leary won a Victoria Cross in northern France in February 1915.

While serving with the Irish Guards, he took out two different German machine gun nests, killing eight soldiers while taking two others prisoner. Lance Cpl O'Leary was hailed as a hero and his fame was exploited to aid the recruitment effort in Ireland, where it was markedly slower than in other parts of what was then the United Kingdom.

The story of O'Leary is one of four Irish lives which form the centrepiece of an exhibition at the National Library of Ireland on Kildare Street which will run for the next four years. He represents the thousands of Irish Catholics from a nationalist background who joined the British war effort in the first World War. His father Daniel was no lover of the British, but hated the German burning of the Catholic library at Louvain.

At the other end of the social scale was Capt Norman Leslie of the renowned Anglo-Irish Co Monaghan family, who was killed by a German sniper in October 1914. He went into battle as an officer brandishing his sword. The sword was recovered from the battlefield years later.

His nephew Sir Jack Leslie, now 97, brought the sword to yesterday's launch. He was captured by the Germans in 1940 and was forced marched to a prisoner-of-war camp. Along the way he rested just 50 yards from where his uncle was killed.

The life of Proclamation signatory Joseph Plunkett represents the republican tradition that refused to have anything to do with the war. Among the exhibits is a handwritten pledge he had drafted for the Irish Brigade which Roger Casement tried to raise to fight with the Germans against the British during the war.

The role of the relative is represented by Mary Martin, a mother of 12, from Monkstown, Co Dublin. She lost one of three sons who served in the war and her desperate attempts to locate her son Charlie are depicted in letters that form part of the exhibition.

The exhibition will run until 2018 and will be updated throughout.

Next year's will focus on the battle of Gallipoli. It is partially funded by the British government. British ambassador Dominick Chilcott said at the launch that much of the material in the exhibition "gives one the frisson of almost direct contact with the voices and personalities of the past".