The 20th Century

British soldiers of the Cheshire Regiment in a trench on the Somme, 1916 · John Warwick Brooke (1886–1929) for the IWM. Public domain (PD-BritishGov, pre-1957 Crown photograph). Wikimedia Commons.

Britain entered the 20th century at a high-water mark of national self-confidence. An extensive overseas Empire, a widely respected navy, a large industrial economy and a well-developed political system together made Britain one of the world's foremost powers. This was also a period of active social reform at home. Parliament enacted financial assistance for the unemployed, old-age pensions, and free school meals for the country's schoolchildren; it passed workplace-safety legislation; it tightened town-planning rules to halt the further spread of slum housing; and it strengthened the legal support available to mothers and their children after a divorce or separation. Local government was made more democratic, and — for the first time — MPs received a salary, which widened the practical pool of candidates who could afford to serve in public life.

This period of confidence and reform gave way abruptly to war. The immediate trigger, on 28 June 1914, was the shooting dead in Sarajevo of Archduke Franz Ferdinand of Austria, the heir to the Austro-Hungarian throne. His killing set in motion a chain of diplomatic and military mobilisations that escalated into the First World War (1914–18). While the Sarajevo attack provided the spark, the underlying tinder had been in place for some years: a rising tide of nationalist sentiment across Europe, increasing militarism among the great powers, imperial rivalry, and the clustering of those great powers into two rival alliance blocs.

The war was European in its centre of gravity but rapidly became global in scope. Britain fought as one of the Allied Powers, alongside (among others) France, Russia, Japan, Belgium and Serbia — with Greece, Italy, Romania and ultimately the United States joining later. The entire British Empire was drawn into the fighting: more than a million soldiers from India, for example, served under British command across many theatres of war, and approximately 40,000 of them were killed. Men from the West Indies, from Africa, and from Australia, New Zealand and Canada also served alongside British forces. Against the Allies stood the Central Powers — principally Germany, the Austro-Hungarian Empire and the Ottoman Empire, with Bulgaria joining later. Casualties ran into the millions on both sides, Britain alone suffering over two million killed or wounded over the four years of the conflict. A single British engagement — the opening day of the attack on the Somme, on 1 July 1916 — accounted on its own for roughly 60,000 British casualties.

The fighting ended at 11.00 am on 11 November 1918, with victory for Britain and its allies.

In 1913 the British government made a public commitment to 'Home Rule' for Ireland — a constitutional settlement under which Ireland would gain its own self-governing parliament but would remain part of the United Kingdom. Legislation giving effect to that commitment was introduced in Parliament, and immediately ran into the opposition of the Protestant communities of Ulster, in the north of Ireland, who were prepared to resist Home Rule by force if necessary.

When the First World War broke out the following year, the government shelved any Irish constitutional change for the duration of the conflict. Irish nationalists proved unwilling to wait: in 1916, during the war, an armed rising against British rule broke out in Dublin — known ever since as Easter Rising. The leaders of the Dublin rising were tried and executed under military law. An extended guerrilla campaign against British military forces and the police followed. A peace treaty was reached in 1921, and in 1922 Ireland was partitioned: the six mainly Protestant counties in the north continued as part of the United Kingdom under the name Northern Ireland, while the remainder of the island became the Irish Free State — a self-governing state which in 1949 declared itself a republic.

The partition settlement did not command the support of all Irish residents on either side of the new border, and opposition from those who wanted the island reunified as a single independent state fed decades of political dispute and, in Northern Ireland, a protracted terror campaign. The collective name for the sustained conflict between republican and loyalist communities in Northern Ireland is 'the Troubles'.

The 1920s brought real improvements in living conditions for many British households, with substantial investment in public housing in towns and cities across the country. Those gains were then interrupted in 1929, when the world economy entered the Great Depression. Mass unemployment followed in parts of the UK, but the effects of the downturn fell unevenly. The traditional heavy industries — shipbuilding among the worst hit — contracted sharply, while newer sectors, including the motor-car and aviation industries, expanded into the gap left behind. Prices in general fell, and for those Britons who remained in work the period brought a real increase in household spending power: car ownership in Britain rose from about 1 million to roughly 2 million vehicles between 1930 and 1939, and house-building continued at pace. Culturally the decade was productive — writers such as Graham Greene and Evelyn Waugh produced major work during these years, and the economist John Maynard Keynes published influential theoretical work that would go on to shape macroeconomic policy for a generation. Broadcasting also emerged as a mass medium in this period: the BBC opened its radio service in 1922 and, in 1936, launched the world's first regular television service.

RAF No. 19 Squadron Spitfire pilots at Fowlmere during the Battle of Britain, September 1940 · Stanley Devon (1907–1995) for the IWM (CH 1370). Public domain (PD-UKGov, pre-1957 Crown photograph). Wikimedia Commons.

Adolf Hitler took power in Germany in 1933. He regarded the peace terms imposed on Germany by the Allies after the First World War as unjust and was openly committed to territorial expansion for the German people. Over the years that followed he engaged in a systematic programme of treaty renegotiation, rearmament, and small-scale probing of the military resolve of Germany's neighbours. The British government tried for much of the decade to avoid another European war. When, in September 1939, Hitler invaded Poland, Britain and France declared war on Germany in response.

The conflict ran at the outset between the Axis powers (fascist Germany, fascist Italy and the Empire of Japan) and the Allies. The principal Allied states at the start of the war were the United Kingdom, France, Poland, Australia, New Zealand, Canada and the Union of South Africa.

Germany had already absorbed Austria and invaded Czechoslovakia before the Polish campaign; after Poland, Hitler moved west, occupying Belgium and the Netherlands. In 1940, German armies broke through French defences and drove the Allied armies before them. It was at that moment of national emergency that Winston Churchill took over as Prime Minister, becoming Britain's wartime leader.

With France on the point of falling, a huge naval evacuation was mounted to bring British and French troops home across the Channel. Civilian volunteers crewing small pleasure boats and fishing boats sailed from Britain to help the Royal Navy lift more than 300,000 troops off the beaches around Dunkirk. Much equipment was abandoned and many lives were lost, but the operation succeeded in preserving the army and allowed Britain to stay in the war. British popular memory coined the phrase 'Dunkirk spirit' from this event.

From the end of June 1940 until Germany turned east and invaded the Soviet Union in June 1941, Britain and its Empire were in effect Nazi Germany's only active opponents.

Hitler wanted to follow up with an invasion of Britain itself, but that required German control of the airspace over the Channel first. Germany therefore launched a concentrated air campaign against the UK — and the Royal Air Force, flying the British-designed Spitfire and Hurricane fighter aircraft, eventually won the resulting aerial contest in the summer of 1940. This air battle became known as the Battle of Britain. Even after the Luftwaffe lost that contest, it continued night-time bombing raids on London and other British cities; that sustained night campaign is known as the Blitz. Coventry was almost entirely levelled in the Blitz and many other urban areas, especially the East End of London, suffered severe damage. The British civilian population's response under sustained bombing — pulling together in the face of adversity — later became associated with the phrase 'Blitz spirit', which remains in current use.

Winston Churchill (1874–1965) was the son of a politician; before being elected to Parliament as a Conservative in 1900 he had served both as a soldier and as a working journalist. In May 1940 he took office as Prime Minister, declined outright to surrender to Germany, and served as the defining British wartime leader under conditions of severe national hardship. He lost the post-war general election in 1945 but returned to office as Prime Minister in 1951. He remained in the House of Commons as an MP until standing down at the general election of 1964. On his death in 1965 he was honoured with a state funeral; in 2002 a BBC poll of the public voted him the greatest Briton of all time. A handful of his wartime speeches are still regularly quoted:

'I have nothing to offer but blood, toil, tears and sweat' — Churchill's first speech to the House of Commons after he became Prime Minister, 1940

'We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender' — Speech to the House of Commons after Dunkirk, 1940

'Never in the field of human conflict was so much owed by so many to so few' — Speech to the House of Commons during the Battle of Britain, 1940

At the same time as it was defending the home islands, the British military was engaged on many other fronts. Japanese forces overran Singapore and defeated the British garrison there, then advanced into Burma, placing India under direct threat. The United States entered the war at the end of 1941 following the Japanese surprise attack on the American naval base at Pearl Harbour in December of that year.

In the same year, Hitler launched the largest invasion in human history, an attack on the Soviet Union. The eastern front became the war's bloodiest theatre, with immense casualties on both sides; in the end Soviet forces held and then began to push the German army back, and the resulting German losses in the east became one of the war's pivotal turning points.

The overall Allied position progressively strengthened. Significant victories in North Africa and Italy were followed, after German strength had been sapped by the Soviet campaign and after the full weight of American forces and materiel had been committed, by a return to the continent from the west. On 6 June 1944 — known ever since as 'D-Day' — Allied armies landed in Normandy in northern France; from Normandy they pressed east through France and ultimately into Germany itself, producing the comprehensive defeat of Germany in May 1945.

The war against Japan was ended in August of the same year, when the United States dropped the newly developed atomic bomb on the Japanese cities of Hiroshima and Nagasaki. Scientists working in Britain under Ernest Rutherford at the universities of Manchester and then Cambridge had been the first to 'split the atom' and had contributed to the wider wartime research programme (the Manhattan Project) in the United States that produced the bomb. With Japan's surrender the war was over.

Alexander Fleming (1881–1955), born in Scotland, moved to London as a teenager and later qualified as a doctor. In 1928, while researching influenza (the 'flu'), he made the serendipitous observation of a mould that killed bacteria — penicillin. The compound was later developed into a usable medicinal drug by the scientists Howard Florey and Ernst Chain, and by the 1940s it was in mass production. Fleming was awarded the Nobel Prize in Medicine in 1945, and penicillin remains in routine clinical use against bacterial infections today.

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