1683: China's Qing Dynasty formally annexes Taiwan, which had previously been divided between indigenous kingdoms and Chinese and European settlers, most prominently the Dutch.

1895: China cedes Taiwan and other territories to Japan after losing the First Sino-Japanese War.

1915: The Tapani Incident prompts Japan to reform its administration of the settled population in Taiwan, which turns to civic and political activity. The Japanese continue to treat the indigenous population harshly.

1930: Troops crush the Wushe Rebellion, the last major indigenous uprising in Taiwan.

1942: The Chinese Kuomintang government renounces all treaties with Japan and demands the return of Taiwan as part of any post-war settlement, which is endorsed by the Allies in the Cairo Declaration.

1945: Taiwan is placed under Chinese administrative control after Japan surrenders.

1947: The 228 Incident, a rebellion against centralized rule by mainland Kuomintang officials, leads to the imposition of martial law, the killing of large numbers of protesters, and the banning of thousands of others from political activity.

1949: The evacuation of the Kuomintang government and about two million refugees to Taiwan following the Communist victory in the Chinese Civil War leads to mainland dominance of the island until the end of martial law in 1987. The Republic of China government in Taiwan retains UN and Western recognition as the legitimate government of all China until the 1970s.

1950s-1960s: Taiwan experiences rapid industrial development and export-oriented policy with support from US economic aid, while the Kuomintang party justifies one-party rule on the grounds of opposing any Communist threat.

1971: The United Nations recognizes the People's Republic of China as the sole government of the whole country after veteran Kuomintang leader Chiang Kai-shek refuses a dual-representation deal.

1996: Free elections result in Lee's victory over the Democratic Progressive Party's Peng Min-ming. The Communist Chinese government tries to disrupt the elections with missile tests, which are countered by the US dispatch of aircraft carriers to the region.

2000: Chen Shui-bian wins the presidential elections, ending the Kuomintang party's 50-year monopoly of power. In his inaugural speech, he declares that he will not call for a referendum on independence or abolish Taipei's official blueprint for eventual reunion with mainland China as long as China does not attack.

2010: Taiwan and China sign a landmark free trade pact, seen as the most significant agreement in 60 years of separation.

2014: China and Taiwan hold their first government-to-government talks since the Communists came to power in 1949. The Taiwanese government minister in charge of the island's China policy meets his mainland counterpart in the eastern city of Nanjing.

2018: Taiwan's legislature legalizes same-sex marriage, becoming the first place in Asia to do so.

2020: The DPP's Tsai Ing-wen is re-elected as president in a landslide victory.

2021: The United States announces plans to sell $1.8 billion worth of arms to Taiwan, including surface-to-air missiles, raising tensions with China.

After the Chinese Communist Party won the Chinese Civil War in 1949, the Nationalist government fled to Taiwan and established a government there. Until 1971, the United States recognized the Nationalist government in Taiwan as the legitimate government of China. However, in 1971, the United States switched its recognition to the communist People's Republic of China. Taiwan is considered a separate country by many due to its self-governance and distinct identity, but China views it as a rebel province.

1922: Ukraine was incorporated into the Soviet Union.

1932-1933: Soviet dictator Joseph Stalin engineered the Ukrainian famine, known as the Holodomor, which resulted in an estimated 3.9 million Ukrainian deaths.

1936-1938: Stalin initiated a large-scale purge of perceived enemies from throughout the Soviet Union, including Ukraine, either executing them outright or shipping them off to Gulag labor camps. 

1941: Nazi Germany invaded the Soviet Union and seized almost all of Ukraine. 

1944: Stalin deported the entire population of Crimean Tatars, and Soviet troops recaptured Ukraine and forcibly deported hundreds of thousands of ethnic Poles as they marched west towards Germany. During World War II, Ukraine suffered an estimated 5 million to 7 million deaths, including around 1 million Ukrainian Jews. 

1954: The Soviet government under Nikita Khrushchev transferred Crimea from Russia to Ukraine.

1986: the Chernobyl nuclear power station in Ukraine experienced a deadly reactor meltdown in a safety test, which is often blamed for hastening the Soviet Union's demise.

1991: Ukraine declared independence from the Soviet Union.

1994: Ukraine gave up its inherited nuclear weapons in exchange for a Russian promise to respect existing borders, and became a major recipient of US foreign aid. 

2004: The Orange Revolution saw pro-Western candidate Viktor Yushchenko win a re-run vote after allegations of fraud in the original election. 

2014: Protestors forced out the Russia-backed President, Viktor Yanukovych, and Russia responded by annexing Crimea and supporting a separatist revolt in the Donbas region. 

2019: Volodymyr Zelensky, a former comedian, was elected President of Ukraine.

2022: Russia launched a full-scale invasion of the country.

The war in Ukraine is an ongoing conflict that began in 2014, following the 2014 Ukrainian revolution and the subsequent annexation of Crimea by Russia. The conflict involves fighting between Ukrainian government forces and pro-Russian separatists in the eastern regions of Donetsk and Luhansk, known collectively as the Donbas. The fighting has resulted in thousands of deaths and has displaced hundreds of thousands of people. 

The Iran-Iraq War was a conflict that took place between 1980 and 1988 and was fueled by religious and political differences. Iran, which is predominantly Shia, had recently undergone a Shia revolution that sought to spread its message and influence across the predominantly Sunni Arab world. This threatened the domestic security of the Sunni-led Baath party in Iraq, and the two countries eventually went to war. 

Sunni and Shia Islam are the two main branches of Islam, with the majority of Muslims being Sunni. The divide between the two dates back to early Islam and is based on a disagreement over who should have succeeded the Prophet Muhammad. Sunni Muslims believe that the Prophet's companions were the rightful leaders, while Shia Muslims believe that leadership should have passed through the Prophet's descendants.

The Taliban is a Sunni Islamist militant group that was founded in Afghanistan in the 1990s. The group rose to power in the mid-1990s and ruled over much of Afghanistan until 2001, when it was toppled by a U.S.-led military campaign. The group has continued to wage an insurgency against the Afghan government and its international allies, and the conflict in Afghanistan has continued to this day. 

Artificial intelligence (AI) is the broader concept of computers being able to perform tasks that normally require human intelligence. Machine learning (ML) is a specific type of AI that involves the development of algorithms that allow a computer to learn from data, without being explicitly programmed.