I shall never forget the August morning in 1991, when I was stationed in the Soviet Union as BBC Moscow correspondent, and was woken early by the BBC news desk to check out a statement that had just turned up on TASS, the Soviet state news agency. It declared that the Soviet President, Mikhail Gorbachev, had been taken ill and a state of emergency imposed. By mid-morning there were tanks rumbling through the city’s main thoroughfares, taking up positions on bridges and around the Kremlin walls, and it was clear that an attempt to seize power was under way by Soviet hard-liners who feared that Gorbachev’s reforms had given too much power away.

What I remember is the extraordinary reaction of local people. Many of them were incredulous, both nervous and yet remarkably unafraid. Our elderly cleaning lady, Masha, made her way out on to the street outside the office, still in her apron and headscarf, and began to scold the soldiers who emerged from the turrets of the tanks, which they had parked on the verge.

‘What are you doing here?’ she rebuked them. ‘You should be ashamed of yourself! Go home to your mothers where you belong!’

Within three days the coup plotters lost their nerve and their attempt to seize power collapsed.

It was one of the most vividly memorable episodes of my life. So much hung in the balance. If this coup by the old guard had succeeded, it would have reinstated Soviet power, reasserted the primacy of the Communist Party and returned the world to a new freeze. Some people find worrying echoes of Cold War antagonism in the more recent mistrustful stand-off between Russia and the West. But if those coup plotters had managed to turn back the clock in August 1991, Cold War tensions would never have abated at all, and we might now be living in a very different world.

I was fortunate to be there at that theatrical turning point. It was a privilege to be a BBC news correspondent reporting from Moscow at that time, a moment of global history in the making. But the events of late 1991 represented only one final scene in a geopolitical drama that spanned the globe and endured for nearly half a century.

Everyone who can count themselves as one of the Cold War generation probably has some searing experience associated with that strange, strained era, which veered from clandestine conspiracies and political brinkmanship to vicious blood-letting and agonising, cataclysmic wars. For those untouched by the devastating proxy clashes and spasms of brutal repression, the Cold War was often a backdrop, neither war nor peace but something running dimly in the background, hidden in twilight hues, in between. But for everyone who lived through those years there were some moments when the magnitude of the conflict loomed out of the shadows and its dramas took centre stage.

Beginning in 1944, even before the Second World War had ended, and lasting until the Soviet Union collapsed at the end of 1991, the Cold War lasted for well over four decades. The initial spotlight was on Europe, but within a few years it had spread to Asia. In time, countries as far apart as Vietnam, Chile and Angola were all caught up in its web.

The tensions that developed into the Cold War grew out of the Second World War and the question of what to do with the war-wrecked lands vacated by the retreating German armed forces. Once the menace of Hitler had been overcome, the wartime alliance between the United States and Britain on the one hand and the Soviet Union on the other began to unravel. Attempts by the Allied powers to agree on a post-war division dominated several summits, starting with the Tehran conference in 1943, Winston Churchill’s private meeting with Josef Stalin in Moscow in October 1944 and the so-called Percentages Agreement it produced, the Yalta conference of February 1945 and, five months later, another three-way summit in Potsdam. But the diplomacy only went so far.

Across Eastern Europe, Soviet troops were moving in and Communist takeovers were swiftly following. The Soviets were keen to take advantage of this opportunity to spread their Communist ideology westwards. They also wanted to make Eastern Europe a buffer zone to protect themselves against any future incursions from Germany or any other part of Europe.

Western powers, alarmed by the speed with which the Soviets were occupying territory, began to coalesce around a series of policies to contain the advance. The Truman Doctrine of 1947 sought to counter the expansion of Soviet geopolitical influence. The Marshall Plan poured billions of dollars of American aid into Western Europe to rebuild it after the war. The NATO military alliance followed in 1949, a collective defence pact to act as a counterweight to the threat posed by Soviet armies stationed in Eastern Europe. Within a few short years of the end of the Second World War, Europe once again found itself to be a conflict zone, not this time for a fighting war, but as the central focus of an ideological and political split, with the divided city of Berlin at its heart. And instead of Britain, France and Germany dominating the continent’s diplomatic chessboard, now the leading powers facing each other across the divide were the United States and the Soviet Union.

From 1949, the Cold War spread further round the globe with the emergence of another Communist giant – Mao Zedong’s ‘Red’ China. The disclosure, that same year, that the Soviet Union had acquired atomic weapons, and the start of the Korean War in 1950, brought tensions to a new peak. Revelations of Soviet espionage and fears of infiltration whipped up an anti-Communist crusade in the United States. Strident anti-capitalist rhetoric and paranoia about all things Western accompanied a new wave of Stalinist repression inside the Soviet Union, while in Eastern Europe new Communist regimes set about murdering and jailing their enemies. And even though the death of the Soviet leader Joseph Stalin in 1953 brought hopes of a thaw and better East–West relations, that did not last. The violent suppression of an uprising in Hungary in 1956 and a crisis over the stationing of Soviet missiles in Cuba in 1962 served as reminders that the world was staring into an abyss, caught between two global systems that viewed each other as mortal enemies and which could all too easily slip into nuclear war.

It was a privilege to be a BBC news correspondent reporting from Moscow at that time, a moment of global history in the making.

The 1960s brought new dramas in Europe with another uprising brutally suppressed by Moscow – in Czechoslovakia in 1968 – but the global ramifications of the Cold War continued. The two major Communist powers, China and the Soviet Union, fell out, and the United States found itself embroiled in an unwinnable war against Communists in Vietnam.

By the 1970s, the division of Europe had become a fact of life, codified into a ‘new normal’ by the process of détente and an ‘Eastern Policy’ – ‘Ostpolitik’ – to foster better links between the two sides of a divided Germany. But if the old battleground of Europe adjusted to a ‘cold peace’ and both superpowers agreed that any conflict involving nuclear weapons had to be off limits, this did not mean that the era of confrontation was over. Far from it. In Europe, the Cold War remained a conflict of nerves, but in Asia, Africa and Latin America it erupted into bloodstained battles, as the big powers fuelled and engineered a series of coups and civil wars, acting out their rivalry in distant proxy conflicts.

The denouement of this four-decade-long drama came unexpectedly in the mid-1980s, largely as the result of a change of leadership in the Soviet Union. Few people anticipated that the challenge that would overturn Soviet Communism and destroy its empire would come from within. But within six short years, the reformist Kremlin leader Mikhail Gorbachev overturned preconceptions and overhauled the Soviet Union’s internal and global relations, leading to the abrupt collapse of Soviet rule, first in Eastern Europe and client states elsewhere, and then also inside the Soviet Union in December 1991.

The story of the Cold War did not end there. For many Soviet citizens, especially those in Russia, the overnight erasure of their country from the map was a terrifying cataclysm and a source of trauma from which it would take years to recover. Many of them agreed with their subsequent President, Vladimir Putin, that the end of the Soviet Union was a great tragedy and a terrible loss. And geopolitical tensions between East and West did not entirely disappear. In later years, they would re-emerge in disagreements and even conflicts, like the long-lasting, simmering war in eastern Ukraine, caused in part by unfinished business left over from the Cold War years and the Soviet Union’s hasty disintegration.

But what happened in December 1991 did at least confirm that the confrontation that had dominated the globe since the end of the Second World War was over. And the extraordinary ideological battle between two very different philosophies, Communism and capitalism, which split Europe and the world in two for most of the second half of the twentieth century, was finally at an end.

As for those who were participants, on one level the story of the Cold War must be seen as a strategic fight for territory and power, the responsibility of those involved in warfare and diplomacy, the preoccupations of soldiers, spies, diplomats and members of political elites. But in almost every country its impact was also felt by ordinary citizens. This was a battle between two opposing systems, waged on a global stage, disrupting the lives of millions of people. Many of them found themselves with ringside seats and pivotal roles as key episodes unfolded, and sometimes with heart-rending personal experiences to relate.

In this book, it is their stories that we want to bring you: the personal perspectives of people who happened to be present at key events, sometimes as spectators, sometimes as actors, sometimes as unwitting chroniclers. These are the unsung foot soldiers of the Cold War. And their powerful accounts of what they saw with their own eyes offer a vivid taste of what this multifaceted and long-lasting conflict really felt like when experienced close up.

Some of our testimonies come from people who were small children at the time: the eight-year-old Greek boy, sent out on the streets by his father to experience what was happening, as the Battle of Athens unfolded in December 1944; the six-year-old girl in East Berlin whose main worry during the East German uprising of 1953 was whether her birthday party would go ahead as planned.

Some of our eyewitnesses were young adults whose experiences scarred them for life: the young North Korean researcher who fled south during the Korean War but then found himself unable to go back, and never saw his mother again; the young Japanese fisherman who happened to be on the edge of the blast zone when the first hydrogen bomb was detonated on a Pacific atoll; the two brothers who were forced to stand helplessly by while their father was hounded to his death by their classmates during China’s Cultural Revolution; and the young US soldier who discovered to his horror that what he thought would be America’s fight for South Vietnamese freedom had degenerated into the indiscriminate murder of Vietnamese civilians.

Some of our stories come from people who happened to find themselves at the heart of events: a British soldier who saw a sniper’s bullet whistle past him and nearly kill Winston Churchill; the young son of the Soviet leader Nikita Khrushchev, watching his father react to the fact that the volatile tyrant Joseph Stalin was dead; the student standing next to Chile’s first ever Socialist President, Salvador Allende, as he made his final speech before being bombed by his own armed forces, under the direction of his chief of staff, General Pinochet; and the Russian tank commander who resolved to ignore orders to use violence against protestors during that fateful attempted coup in Moscow in August 1991.

And some of the testimony comes from people who had no intention of being caught up in the heat of the action but who found the Cold War drew them in anyway: the Hungarian student who joined a peaceful demonstration and within 24 hours found himself armed and amid a revolution; the Gdańsk shipyard worker who described how Lech Wałęsa’s late arrival for a strike protest lit the spark that ignited the Polish Solidarity movement; and the young British mother, appalled at the thought of nuclear armed cruise missiles being installed at an American airbase near her village, who scaled the perimeter fence in protest.

Through this book and the BBC Radio 4 series, Cold War: Stories from the Big Freeze, which it accompanies, many of these stories are being shared with a wider public for the first time, and we give those who spoke to us our heartfelt thanks for agreeing to take part. It is a kaleidoscope of richly varied reports, wide-reaching, sometimes distressing, sometimes even joyful, and always intensely personal. In gathering and processing the material, we were all profoundly affected by these accounts. We hope you will be too.