The South Sea Bubble

The South Sea Bubble of 1720 remains the original blueprint for speculative ruin, with shares surging from £128 to over £1,000 before collapsing to £135—wiping out thousands including Sir Isaac Newton, who lost £20,000 (over $3 million today). This mania is 50% more devastating than the average 18th-century market crash in terms of investor participation, with Parliament itself implicated in insider trading. The bubble's cautionary legacy outperforms #9 Theranos by inflicting losses that reshaped financial regulation for centuries.