The British Empire, which spread across the globe between the 17th-20th centuries came crashing down after WW2, but the beating heart (or perhaps the brain) of that Empire, the City of London, survived and re-invented itself as a different sort of financial superpower. The City “manages” many of the world’s major off-shore tax havens, which are UK overseas territories (Bermuda, Cayman Islands, British Virgin Islands, Gibraltar, Jersey, Guernsey, Isle of Man etc etc). Via the English common law system of Financial Trusts, the global elite has secreted countless trillions of dollars in these tax havens, safe in the knowledge that the British government guarantees their assets without asking any difficult questions.
Not mentioned in the documentary, which is very watchable by the way, is the corollary of how, when the Roman Empire collapsed, it also reinvented itself and kept Rome at the forefront of global affairs for the next 1500 years – through the influence of the Roman Catholic Church.
h/t Sabremesh