Colour-Sergeant M.C. Keane was just 24 on January 22, 1879 when he fell during the first major battle of the Anglo-Zulu War.
For more than a century his body lay anonymously near the mass graves of more than 1,300 colleagues who also lost their lives in Britain's bloody defeat at Isandlwana, in what is now South Africa.
But historians have now finally been able to identify his remains after archaeologists unearthed a tunic button on his skeleton.
Historian Arthur Konigkramer said the distinctive metal badge was that of the General Staff Corps - and the only soldier from that regiment who fought at Isandlwana was Colour-Sergeant Keane.
He added: 'This is a truly remarkable discovery.'
The metal badge was discovered with Colour-Sergeant Keane's skeleton in April during excavations by Amafa, the heritage organisation responsible for protecting the historic battle field 100 miles north of Durban.
Archaeologists found it as they dug out the foundations of guards' accommodation.
A photograph of the badge was emailed to British military medal expert John Young in London, who identified the markings and the soldier it belonged to.
Amafa spokesman Mr Konigkramer said the finding had helped historians build up a clear picture of what had happened to the young Colour-Sergeant during the bloody battle, in which around 1,350 British troops were slaughtered by 22,000 Zulu warriors.