Russian President Vladimir Putin launched the biggest invasion in Europe since World War II when he sent troops into Ukraine on 24 February this year to "demilitarize and de-Nazify" the country, causing millions of Ukrainians to flee abroad.

The West imposed unprecedented sanctions on Moscow and sent billions of dollars in aid to Ukraine, which repelled Putin's bid to capture the capital, Kyiv and topple the government of President Volodymyr Zelensky.

In the south, however, Russian forces captured most of Ukraine's Black Sea coastline, including the port of Mariupol, which was destroyed in a three-month siege.

In April, Russian forces were accused of massacring scores of civilians in the Kyiv suburb of Bucha.

By September, Ukrainian forces were regaining ground in the northeast and south. Putin hastily annexed four Russian-controlled regions, a move condemned as illegal by the United Nations.

In November, Ukrainian forces chalked up their biggest victory yet when Russian forces retreated from the southern port of Kherson, ending an eight-month occupation.

From the Russian invasion of Ukraine to the overturning of abortion laws in the United States, here is a roundup of the biggest events to mark 2022.

Nightmare on Downing Street

Britain got its fifth conservative prime minister in six years.

Rishi Sunak took office in October after his tax-cutting predecessor Liz Truss self-combusted in just 44 days — the shortest-ever tenure for a British leader.

Truss's lightning fall from grace, sparked by a disastrous mini-budget, capped a tumultuous 2022 in Britain. The year is marked by the death of its longest-serving monarch, Queen Elizabeth II, at the age of 96 and the forced resignation of Brexiteer premier Boris Johnson after a series of scandals.

US abortion shock

The US Supreme Court caused global shockwaves in June when it overturned its landmark 1973 "Roe v Wade" decision enshrining access to abortions nationwide.

Following the ruling, abortion bans were brought in by Republicans in 16 US states, home to 26.5 million women.

The issue impacts November's midterms.

There were smaller-than-expected gains for Donald Trump loyalists in the Republican camp, as US voters in several states sided with candidates advocating access to abortion. Trump nonetheless announced he will stand again for president in 2024.

Xi cements control

President Xi Jinping cemented his control at the helm of China after winning a historic third term in November as leader of the world's second-largest economy.

But the Chinese have lost patience with the snap lockdowns, mass testing and curbs on movement occasioned by his signature zero-Covid strategy.

Thousands of people took part in several days of protests against the restrictions in Beijing, Guangzhou, Shanghai, Urumqi, Wuhan and other cities. Some even dared to call for Xi's resignation.

Xi's increasingly unchecked power also caused alarm in Taiwan, after China staged massive military exercises around the island.

Heatwave after heatwave

Europe weathered the hottest summer in its recorded history, with the mercury topping 40 degrees Celsius (104 degrees Fahrenheit) for the first time in Britain.

Parts of the Arctic and Antarctic, China and the US also experienced record temperatures. Extreme weather events linked to climate change continued to wreak havoc in developing countries.

Flooding in Pakistan affected vast swathes of the country, with Nigeria suffering its worst floods in a decade and parts of drought-hit Somalia facing the threat of famine.

At the United Nations climate summit in Egypt or COP27, developing nations finally succeeded in getting wealthy polluters to agree to pay into a "loss and damage" fund to compensate poorer countries for climate damage.

Inflation bites

The invasion of Ukraine and resulting sanctions on Russia create an energy crisis of a magnitude unseen in half a century, with costs for gas and electricity soaring globally.

Britain sees its energy bills double over the space of a year. Soaring energy prices are also a factor in Sri Lanka's cost-of-living crisis, which in August forces then-president Gotabaya Rajapaksa to flee abroad.

Inflation soars globally, prompting central banks to aggressively hike interest rates, raising fears of another major debt crisis.

Far-right on the march

The far-right made unprecedented gains in Europe.

Voters in Italy elected their most right-wing leader since World War II in post-Fascist firebrand Giorgia Meloni.

The anti-immigration Sweden Democrats are the big winners of a general election that brings conservatives to power in that country.

In France, a surge by both the far right and hard left strips right-of-center President Emmanuel Macron of his parliamentary majority.

But in Latin America, the right is in decline.

Veteran left-winger Luiz Inacio Lula da Silva made a stunning comeback in Brazil, ousting far-right incumbent Jair Bolsonaro. Left-wing leaders also come to power in Colombia and Honduras.

Iran's great unveiling

In Iran, the death of 22-year-old Mahsa Amini following her arrest for alleged violations of the country's Islamic dress code sparks the biggest protests in years.

On the street and on social media women and girls defiantly remove their headscarves in an unprecedented challenge to the country's clerical leadership.

Iran sought to quell the protests by sentencing some of the protesters to death.

Over 300 people had been killed in the unrest, the authorities said on 29 November. This week, Iran announced the abolition of its morality police.

Peace in Ethiopia

After two years of conflict that have killed untold numbers of civilians and led to near-famine conditions in Tigray, Ethiopia's government and Tigrayan rebels agreed on a landmark peace deal.