A largely unknown painting which profoundly impressed the poet Wilfred Owen will be one of the highlights of a new exhibition at the Scottish National Portrait Gallery, marking the centenary of the outbreak of the First World War.

Avatar, an elegiac meditation on the fallen of the War, painted by Henry Lintott in 1916, was seen by Owen while he was being treated for shell shock at the Craiglockhart War Hospital in Edinburgh in 1917. He was moved to describe the work, which depicts a deceased warrior, covered in a black shroud, being carried to heaven by four ethereal figures, as the ‘finest picture now in the Edinburgh Gallery.’ Avatar, which will be on loan from the Royal Scottish Academy has only been on show to the public a handful of times since the War, and has been specially conserved with the aid of a grant from AIM and the Pilgrim Trust Award, to feature in the exhibition.

Remembering the Great War, which opens at the Portrait Gallery on 4 August, will make a significant contribution to this year’s global commemorations. Largely drawn from works in the National Galleries of Scotland collections, the thought-provoking and poignant selection of portraits and related images will reflect the stories of a wide range of people, from famous figures to ordinary men and women, and the many different ways in which their lives were touched by the conflict.

The exhibition will feature depictions of senior statesmen, military figures, writers, poets, painters and musicians, and photographs of servicemen and women, as well as preparatory drawings for the Scottish National War Memorial at Edinburgh Castle. It will also include a remarkable group of etchings inspired by the war experiences of the German artist Otto Dix.

Remembering the Great War will begin with an exploration of some of the significant figures who played a part, as both proponents and opponents, in the run up to the outbreak of war. These include a striking portrait of King George V by Charles Sims and an oil study of Field Marshall Douglas Haig, 1st Earl Haig, by John Singer Sargent. Portraits of the Scottish socialist and Labour leader James Keir Hardie, and the first Labour Prime Minister James Ramsay MacDonald, represent those who were strongly opposed to the war.

The exhibition will also address issues connected with the role of women and the war effort, touching on the social changes brought about by the conflict and the opportunities it gave to those at home. Among the women represented here are Flora Drummond, a militant figure in the Suffragette movement which on the outbreak of hostilities put on hold its demands for emancipation to support the war; and the poet and children’s author Lady Margaret Sackville who published The Pageant of War, a collection of anti-war poems in which she declared that women who supported the war were betraying their sons.

Also on display is a collection of significant figures in the Scottish artistic landscape at the start of the 20th-century. These include the music hall artist Sir Harry Lauder, described by Winston Churchill as ‘Scotland’s greatest ever ambassador’ for his contribution to the entertainment of troops, who tragically lost his only son in France; artist William McCance who was imprisoned as a conscientious objector; and Lord Reith, later the Director-General of the BBC, who fought with distinction for the 5th Scottish Rifles and was shot in the face by a German sniper, sustaining the famous scar clearly visible in his portrait by Sir Oswald Birley.

The exhibition will also reflect the contribution of Scottish people to the medical response to the war through figures such as Mary Garden, an opera singer who worked as a nurse after failing in her attempt to enlist, disguised as a man, in the French army; Dr Elsie Ingles, who helped to establish the Scottish Women's Hospital for Foreign Service Committee, and served in field hospitals in Serbia (where she was captured) and Russia; and Sir Alexander Fleming whose service in the Army Medical Corps informed his later research and subsequent discovery of Penicillin.

Images of nurses and wounded men on the wards of Springburn Hospital in Glasgow are among the fascinating selection of photographs in the exhibition, which also includes a series of prints by George P. Lewis, who was commissioned by the Women’s Work Committee for the Imperial War Museum in 1918, to document the role of Scottish women in transport and heavy industries during the war.

Contemporary photographs by Scottish photographer Peter Cattrell shift our wartime reflections into the present, with haunting black and white images of the Somme battlefield in France as it stands today, still bearing the scars of war. Cattrell has also depicted the spot where Wilfred Owen died on 4 November 1918. Born in Glasgow in 1959, Cattrell’s interest in the Somme took flight after discovering a photograph of his great uncle, William Wyatt Bagshawe, who died on the first day of the Somme in July 1916. Some 57,000 men were killed on that day alone.

Within the exhibition space, a projected display of images of unidentified servicemen and women reiterates the important point that the Great War profoundly affected society as a whole, leaving nobody untouched.

Christopher Baker, Director of the Scottish National Portrait Gallery said: “Our hope is that this moving exhibition will remind our many visitors of the terrible sacrifice and enduring impact of the Great War and the special role that Scotland played.”