The last time the people of Great Britain were called to the polls to voice their views on their relationship with Europe, a landslide majority chose to stick together with the continent. Yet, the public debate was as polarized as it's been this time around. as Britons head to the polls to determine whether they will leave the European Union.
For anthropologist Edmund Leach, for example, the anti-Europeans of the time were misty-minded isolationists who showed "the same degree of contact with rational probability as a New Guinea cargo cult," as TIME reported in June of 1975. Meanwhile, in the same story, playwright John Osborne called joining with Europe "the last desperate dream of dull, dim tradesmen without vision, imagination or self-respect, feeling for life or history."
A few days later, 17,378,581 people voted to embrace Europe's Common Market, the precursor to the European Union.
As the fate of the European Union is once again in the balance, we take a look back at the contentious campaign of the early 1970s when Great Britain seemed as divided about its future as it is today.
Michelle Molloy, who edited this photo essay, is a senior international photo editor at TIME.