20 Times People Majorly Screwed Up And Changed The Course Of History

A misplaced key that sank the Titanic. Failing to sign the Beatles. Losing a vital Civil War battle plan. They’re all horrible errors that changed history. It’s normal to make mistakes — we all do it. Thankfully for most of us, the errors we make are of small consequence. But spare a thought for those whose mistakes altered history — often disastrously…

20. A plague on both your houses...

Back in 1348 Scots chieftains were delighted to hear that the “auld enemy” — England — was in the grip of a devastating plague outbreak. For the more bellicose Scottish people this presented an opportunity too good to be missed. Surely, now was the perfect time to invade their antagonists to the south, while they were so sorely stricken?

A Scots army duly marched across the border into England in 1349. But the invaders had failed to spot one serious weakness in their plans. If you trample into another nation where plague is raging, there’s every chance you’ll be infected. And surprise, surprise, it seems that’s precisely what happened. Even worse, they apparently took the plague back to Scotland when they retreated, sparking a major epidemic there.

19. Chairman Mao’s bird-brained cull

Mao Zedong, it seems, was often angry at the world. And in 1958 the Chinese leader crystallized this rage into a program known as the four pests. The less-than-fab four were identified as rats, flies, mosquitoes — and the humble house sparrow. All of those creatures were to be killed on sight. The diminutive brown birds were in the frame because they ate crops rightfully bound for human mouths. 

Whatever they thought privately about Mao’s instructions, the Chinese people acted with enthusiastic zeal. One expert estimated that during the period of the campaign as many as 1 billion sparrows were exterminated, pushing them close to local extinction. But Mao had overlooked one key impact of the sparrow massacre: sparrows ate locusts. And lo and behold, China was soon engulfed in a catastrophic plague of the voracious insects, gobbling down food crops at a terrifying rate.