End:30 April 1945

Impacts/Effects: Hitler immediately set about abolishing the powers of the states and the existence of non-Nazi political parties and organisations. Non Nazi parties were formally outlawed on 14 July 1933 and the Reichstag abdicated its democratic responsibilities.

End: July 24 1944

Impacts/Effects: D-Day put the Allies on a decisive path toward victory. Beginning with the Normandy beaches they pushed back against Axis forces until Germany was forced to surrender less than a year later. D-Day gave the Allies a long awaited foothold in Europe and its success led to the continent's liberation and the end of World War II. About 160,000 men took part in the June 6 1944 invasion, about half of whom were American. The U.S. suffered tremendous casualties that day but their valor will never be forgotten.

End: 8,000 B.C.

Impacts/Effects: The Neolithic Revolution greatly narrowed the diversity of foods available, resulting in a downturn in the quality of human nutrition compared with that obtained previously from foraging, but because food production became more efficient, it released humans to invest their efforts in other activities, it was the critical transition that resulted in the birth of agriculture.

End: late 1980s

Impacts/Effects:the production of cereal crops tripled with only a 30% increase in the land area cultivated. This came true all over the world, there were significant impacts on poverty reduction and lower food price

Impacts/Effects: The invention of gunpowder was and is a significant event in human history as it has shaped the styles of warfare at the time while resulting in massive political and cultural change in Europe and beyond such as the eventual collapse of feudalism. Their explosive invention would become the basis for almost every weapon used in war from that point on, from fiery arrows to rifles, cannons and grenades. Gunpowder made warfare all over the world very different, affecting the way battles were fought and borders were drawn throughout the Middle Ages.

End: 1840

Impacts/Effects: shifted societies from an agrarian economy to a manufacturing economy where products were no longer made solely by hand but by machines. This led to increased production and efficiency, lower prices, more goods, improved wages, and migration from rural areas to urban areas. While created economic growth and offered new opportunities, that progress came with significant downsides, from damage to the environment and health and safety hazards to squalid living conditions for workers and their families.

Impacts/Effects: Plastics made possible the development of computers, cell phones, and most of the lifesaving advances of modern medicine. Lightweight and good for insulation, plastics help save fossil fuels used in heating and in transportation.Plastic pollution can alter habitats and natural processes, reducing ecosystems' ability to adapt to climate change.

Impacts/Effects: Columbus's journeys to the Americas opened the way for European countries to colonize and exploit those lands and their peoples. Trade was soon established between Europe and the Americas. Plants native to the Americas (such as potatoes, tomatoes, and tobacco) were imported to Europe. Columbus thereby initiated an era of exploration, subjugation, and colonization that lasted for centuries. The explorer has been accused by many historians of initiating the genocide of Hispaniola's indigenous Arawak population, and he is also considered by some to be the originator of the transatlantic slave trade.

Impacts/Effects: Amid the conflict, many children and families have been forced to flee to safer areas, resulting in considerable internal displacement. Due to the level of poverty associated with migrating populations, the most vulnerable children and their families often end up in slums if they move to urban areas. Civilian displacement and refugee exodus constitute one of the worst humanitarian crises in modern history.

Impacts/Effects: The moon landing taught us about the composition of the moon. It gave us the first perspective of the Earth from Space. Overall, there are many technologies that we now use in our daily lives that we would not have if scientists did not continue to explore space,

Impacts/Effects: The WTO operates the global system of trade rules and helps developing economies build their trade capacity. Global rules of trade provide assurance and stability. Consumers and producers know they can enjoy secure supplies and greater choice of the finished products, components, raw materials and services they use.

Impacts/Effects: Johann Gutenberg's invention of movable-type printing quickened the spread of knowledge, discoveries, and literacy in Renaissance Europe. The printing revolution also contributed mightily to the Protestant Reformation that split apart the Catholic Church. More copies of books, pamphlets, or posters would be printed, spreading ideas.

Impacts/Effects: Facebook Brought People Together. Facebook also made it easy to share memories by letting users post photos and videos and tag people in them. So it allowed people who've met and interacted in real life to keep an online repository of their shared memories, making it easier to reconnect with these people. Facebook enabled $227bn of economic impact and 4.5m jobs globally in 2014

Impacts/ Effects: The idea of political persuasion and data mining suddenly felt very close to every Facebook user, and the aftermath of the scandal included rethinking the ethics of data privacy and the growing impact of social media on electoral politics. Cambridge Analytica still impacts the digital democracy space today.

Impacts/Effects: In winning this battle, the Persians were able to continue their conquest of Greece. They continued marching toward the City of Athens, dominating small towns along the way. Also as a result of their victory at Thermopylae, it spurred their navy to continue their attack upon Greece resulting in the battle of Salamis.

Impacts/Effects: As an attritional offensive, the Battle of the Somme involved heavy casualties on both sides. By the end of the first day on 1 July 1916, British forces had suffered 57,470 casualties, of whom 19,240 were killed. This represented the largest losses suffered by the British Army in a single day. The Allied victory at the Somme despite its horrific cost inflicted serious damage on German positions in France, spurring the Germans to strategically retreat to the Hindenburg Line in March 1917 rather than continue battling over the same land that spring.

Impacts/Effects: The two atomic bombs dropped on Japan in 1945 killed and maimed hundreds of thousands of people, and their effects are still being felt today.

By the end of 1945, the bombing had killed an estimated 140,000 people in Hiroshima, and a further 74,000 in Nagasaki. In the years that followed, many of the survivors would face leukemia, cancer, or other terrible side effects from the radiation.

 The uranium bomb detonated over Hiroshima on 6 August 1945 had an explosive yield equal to 15,000 tonnes of TNT. It razed and burnt around 70 per cent of all buildings and caused an estimated 140,000 deaths by the end of 1945, along with increased rates of cancer and chronic disease among the survivors.

A slightly larger plutonium bomb exploded over Nagasaki three days later levelled 6.7 sq km.  of the city and killed 74,000 people by the end of 1945. Ground temperatures reached 4,000°C and radioactive rain poured down.