War and Game

There are several myths about this battle which have recently been exposed, but the most common one is that the reason the British lost and were wiped out was because the quarter-masters responsible for issuing ammunition refused to do so without the required chits signed by senior officers and so the troops ran out of ammunition. [1]
A slight variation on this story was that the quartermasters issued the ammunition but nobody had the required screw-driver to open the boxes.

Both these myths have since been exposed as inventions of the imagination created to explain the inexplicable without actually placing the blame on anyone important.

In fact, battlefield archeologists have conducted a thorough survey of the Isandhlwana battlefield and discovered a far more plausible explanation based upon the distribution of cartridges and other battlefield debris.

It appears that contrary to the official version of events, the British did not form up in a dense battle line just beyond their camp to receive the Zulu attack, nor did they form gallant squares and fight to the last man as their ammunition ran out. Though this obvious would be what the gold braid at Horse Guards wanted to believe, and so they assumed that this must have been what happened.

However, based upon the distribution of cartridge cases and other battlefield debris across the battlefield it seems that rather than forming a battle line close to the camp the British troops were ordered to advance in skirmish order towards the Zulu army. This was actually hidden beyond a ridge, and the theory is that the intention was to advance up to the ridge line and use it as an initial firing position from which to reduce the strength of the approaching Impii's.

Whatever the intention, the plan went horribly wrong as it appears the Zulu's reached the crest of the ridge just as the British skirmish line was climbing the last few yards before the summit. The first British cartridge cases were found scattered across the front face of the ridge not in dense lines but in dispersed patterns.

It appears that panic immediately set in, as the Zulu's hurtled over the crest and down the slope towards the scattered British troops. Almost immediately the archeologists began to find evidence of discarded equipment. Haversack buckles, rifle mechanisms (some clearly jammed), cap badges were found all the way from the ridge back to the main camp site. Suggesting that the British fell back rapidly in some disorder, and just kept going. There were occasional dense concentrations of cartridges, equipment and uniform remnants in dips and wadi's suggesting that some groups of men had turned at bay and tried to hold positions before being overrun, but the vast majority of the men seem to have started running and never stopped, and cartridge cases were scattered in a wide and dispersed pattern right through the camp and for a mile beyond it as the last survivors were chased and harried to extinction.
At no point was there any evidence of a formed battle line or a gallant square, the last debris found was a few pitiful scraps of uniform and buckles scattered in a dry stream bed over a mile from the battlefield site, where presumably the last survivors, out of ammunition and too tired to run farther were caught and slaughtered.

Bad leadership and even worse intelligence. The British didn't even know where the Zulu Army was. Lord Chelmsford had taken the main body of his force off looking for the Zulu Army.

The Zulus were written off as ignorant savages but it is interesting to note that rather than attack Chelmsford’s main column they instead chose to attack his base camp and later that day Rorke's Drift. i.e. Chelmsford's communication and supply route.

Also the British rifles would be prone to jamming which normally wouldn't have been an issue when the British were in tight formation. In a skirmish line where the men were 10-15 yards apart, a jam would be deadly for the individual concerned and would further weaken an already difficult position.

[1]The reason most of the ammunition boxes were found intact in the camp, giving rise to the myth, is not that nobody had the right paperwork, or a screwdriver (in fact it was shown that one hefty slap with a rifle butt opened an ammo box easily anyway), but simply that they were running for their lives with a bunch of screaming Zulu's on their tails and hadn't got the time or inclination to stop and draw fresh ammunition.