On a January afternoon in 1879, the South African great plain of Isandhlwana lay motionless under a partially eclipsed sun. Beneath the eerie light lay the bodies of 1,329 soldiers, many from Oxfordshire, of the 1/24th Welsh Regiment, slaughtered by 25,000 Zulu warriors.

The battle of Isandhlwana was the worst British colonial defeat recorded, followed the same day by one of the bravest of colonial battles when advancing Zulus were held at Rorke's Drift, ten miles away, by 139 British troops.

The heroism and bloodshed lives on today in stories from both British and Zulu descendents, beside sprinkled white stones across the plain that mark the graves. In 119 years they have never been desecrated. It is a tribute to opponents who respected each other's bravery even in conflict.

"The Zulus loved the British and the British always portrayed the Zulus as people of great nobility and dignity," says David Rattray, an Honorary Fellow of the Royal Geographical Society and renowned authority on the Anglo-Zulu Wars.

"This was a campaign that should never have happened, brought about by a little official given too much carte blanche."

As every war has a tale, every tale has its storyteller, and David Rattray is one of the most even-handed, evocative chroniclers. He tours the world and the battlefields near his home in KwaZulu Natal, South Africa, recounting in compelling English and Zulu narration the circumstances, defeats and triumphs of Isandhlwana and Rorke's Drift.

His latest tour includes Oxford's Sheldonian Theatre on Wednesday. His stories have moved grown men to tears with their poignancy and passion, this is far from a dry history lesson.

The Zulu Wars are about pathos and fact, about the British and the Zulus and about the living and the dead. Ultimately they're about blood spilled on the plains that sweep before David Rattray's front porch.

Rattray was raised on this land and history, steeped in Zulu custom, fluent in Zulu and Afrikaans. His overview canvas is painted with finer marks of detail to bind attention in a thought-provoking, moving way. Because, for Rattray, this is living history. He talks of going to the valley with childhood friend, mZonjani mPanza to collect their old Zulu friend, mNandi nGobese. mNandi's father had commanded a wing of the inGobamakhosi regiment.

They would ask him: "Show us what your father showed you. Tell us what he told you."

mNandi would sit where the battle of Isandhlwana was won and lost, describing Zulu warriors hiding in the long grass, and the rallying cry of a chief as he ran to the front line: "Hey, you over there, don't you dare run away. Our king, Cetewayo, never told you to run away." A British bullet caught the chief between the eyes, but his bravery so moved the Zulus that none backed away. British commanding officer Durnford is remembered by the Zulus as laughing and joking with his men in the midst of Isandhlwana. He was one of the last to die.

The respectful memory goes: "Those red soldiers at Isandhlwana, like lions they fought and like stones they fell."

At Rorke's Drift, Rattray illuminates the courage of the British soldiers, many of whom won VCs.

The 139 men, holding out against 4000 Zulu, made defences from lead-lined biscuit boxes from the stores. One Welshman wrote to his mother afterwards: "Those army biscuits can stop anything!" When battles are fought, written accounts always lean to one side. Memories slip into history's shadow under the victor's light. But in stories the full dynamics of war in both political and human terms remain, and it's in the power of words to move that David Rattray places his faith.

"The British are more open to being told another's point of view. They're transported and moved by these stories. They're blessed with a sense of fairness and they should be proud of it," he says.

David Rattray's Sheldonian lecture is on Wednesday at 7.30pm. For ticket details call 01865 798600 *Did your relatives fight at the Battle of Isandhlwana? We want to tell their story. Call 01865 425404