In 1928, the discovery of penicillin by Fleming begins a new era in antibiotics. While the idea of vaccination against disease goes back to at least the late 1700s (with a vaccine against small pox), and the healing properties of certain molds (penicillin is a kind of fungus) were known in traditional herbal medicine, the new generation of penicillin- based drugs would become the key method to combat disease after the Second World War.

DDT, invented in 1939, becomes one of the most widely used chemical pesticides during the 1940s and 50s. It also was one of the first chemicals to make people aware about the environmental effects of pesticides and herbicides. The first noticeable effect was on bird populations, especially birds of prey. DDT made their eggs fragile and most did not hatch, but sudden declines in the song bird population also caused alarm among the few people who then bothered to monitor wildlife populations. DDT also proved to be toxic to humans, but the effects took longer to show up. DDT is still used widely around the world, although it has been banned in many countries.

In 1937, the Republic of Ireland, also called Eire, declares its full independence from England ending more than 300 years of colonial rule. The Irish fought a war of liberation between 1919 and 1921, winning partial freedom. Northern Ireland, however, remains under British rule.

The Second World War is usually said to have begun with the German invasion of Poland on September 1, 1939. The war grew to include most of the countries of Europe, Asia, North America and Africa. Click here for a list of major events.

An American, Varian Fry, helps 4000 people escape from Nazi-controlled France between the summer of 1940 and the summer of 1941. These included many famous artists, such as Marc Chagall, Jacques Lipchitz and Max Ernst. Fry died in 1967, but only in the early 1990s were his heroic deeds recognized.

The Holocaust becomes the largest genocide of the 20th century. According to racial theories of the Nazi leaders, Hitler, Himmler, Borman, all supposedly inferior races had to be eliminated. The main target were the Jews of Europe--but here the underlying idiocy of the Nazi racial doctrine can be seen, since Judaism is a religion and not a race and people of many different ethnic backgrounds follow Judaism. But all groups considered undesirable by the Nazis were sent to the concentration and death camps, including Slavs, Gypsies, physically or mentally disabled, homosexuals and political opponents. The accepted number of people murdered between 1939-45 is 6 million, but the exact total is not known. For example, not included in this total are Russian prisoners of war. In the first year of the German invasion of the Soviet Union (1941), some 3 million Russian prisoners of war were captured, but of this number about 2 million were killed outright or worked to death in slave labour camps--the exact fate of these people will probably never be known.

The total defeat of Germany and its allies in May 1945 left Europe shattered. Millions of people had been killed. Millions more were refugees. Industry and agriculture were devastated. The war left two world powers, the United States and the communist Soviet Union. The United States was dominant in western Europe, while the Soviet Union occupied eastern Europe. The two allies were soon enemies resulting in what was called the Cold War. Two opposing military alliances were created, NATO centred on the United States and the Warsaw Pact, dominated by the Soviet Union. Nuclear war was a serious threat for the next 40 years after 1950. Tension was high in Germany, which was split into two halves, the democratic West and communist East, but was especially high in Berlin. The split between East and West was symbolized by the Berlin Wall, built by the communists in August 1961.

A few of the major names in European art at this time include Lucian Freud (born 1922). A grandson of Sigmund Freud and born in Berlin, Lucian moved to England with his family in 1931. Specialist in portraits and nudes, Freud paints in a realistic manner, but with a distinctive technique that cannot be easily classified. David Hockney (born 1937), has become the best known British artist of his generation. He was at first put into the Pop Art movement, but he himself never considered himself part of this group and has since developed a more traditional, representational style of painting.