Five sketches, which were left unpublished for a century, show Irish nationalist hero Roger Casement in the Tower of London just days before his execution in 1916.

Casement was captured after landing in Ireland from a German submarine and indicted for high treason. Caesment was convicted following a three day trial at the Old Bailey in London and sentenced to execution by hanging in Pentonville Prison on August 2, 1916.

The images were drawn in 1916 on May 9 and 11 by Major John Bernard “Jack” Arbuthnot, an officer in the Scots Guards and also an amateur artist, cartoonist, and part-time journalist, reports the Independent.

One of the drawings shows him reclining on a bench with one leg crossed under him as the other hangs down, revealing a ragged trouser and a battered boot without shoelaces. The sketch reveals how Casement had not been allowed to change his clothes after he was arrested in an effort to demoralize him. His laces, necktie and braces were taken from him to prevent a suicide attempt.

“The images are so important because they are the only ones of Casement in the Tower and the first of him in captivity,” says Angus Mitchell, a lecturer at Limerick University and the author of "16 Lives: Roger Casement," the recently published biography of Casement.

Writing for the Independent, Patrick Cockburn, Arbuthnot’s grandson, says that Major Arbuthnot was stationed in Whitehall in London in 1916 when he was put in charge of supervising Casement’s meetings with his lawyer, George Gavan Duffy, in the Tower.

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“Major Arbuthnot evidently had sympathy for Casement because he expanded his authority by telling the prisoner’s cousins, Gertrude and Elizabeth Bannister, who had been desperately searching for him, where he was imprisoned.

“Gertrude later recorded that ‘we saw a certain Major Arbuthnot who showed courtesy and sympathy,’” writes Cockburn.

“He contacted the Governor of the Tower for them so they could visit Casement and told them to send in clothes for him. During their visit, the Major brought Casement to see them and ordered the two soldiers guarding him out of the room while the Bannister sisters spoke to him.

“Their meeting must have been just after Major Arbuthnot sketched Casement on May 9 and 11, when he met George Gavan Duffy and was still wearing the same clothes, described as being by now filthy and verminous, which he was wearing when arrested at Banna Strand in Kerry on April 21. Four of the drawings are in pencil and one is in pen and ink and all are signed and dated by Major Arbuthnot with brief captions about where and with whom Casement is pictured.”

Soon after the sisters saw Casement, he was moved to Brixton prison and then to Pentonville, where he was executed.

In the so-called “Black Diaries,” which may or may not have been forged, Casement describes his life as a homosexual.

The diaries were used by the British government to damage his reputation and undermine the efforts to prevent his execution.

Cockburn says he remembers seeing one of the Casement drawings when he was a child, but did not understand their significance. He explains why the sketches remained unknown for 100 years.

“The reason the sketches remained unknown is that Major Arbuthnot himself did not care about their historic significance and kept them in Myrtle Grove, his Tudor house in the town of Youghal in Ireland, where he died in 1950. He was well-off and never sold any of his numerous drawings, paintings and cartoons, though they are of high quality. He was a High Tory who lived by his own rules and considered his kindness to Casement in the Tower as very much his own business.”

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