Trump's election as the 45th president of the United States rocked Washington's political establishment and sent shock waves overseas, as US allies and foes alike scrambled to understand how the real-estate mogul and political outsider had pulled off an upset victory and would change their ties to the world's most powerful country.
South Korea called a meeting of its National Security Council as Japan's top financial officials huddled amid a 1,000-point plunge in the Nikkei stock market. Markets in the UK and France also dropped.
US futures also plummeted, as international observers grappled for analogies and images to convey their discomfort, dismay and disgust. Many referred to the shock of watching Britain vote to leave the European Union in a June referendum -- the so-called "Brexit."
"After Brexit and this election, everything is now possible. A world is collapsing before our eyes. Dizziness," France's ambassador to the US, Gerard Araud, said on Twitter.
Former Swedish Prime Minister Carl Bildt also invoked Brexit on Twitter, saying, "looks like this will be the year of the double disaster of the West."
As the election started, the German newspaper Die Welt reproduced the poster for the film "Apocalypse Now," but with Trump's head photoshopped in above the film's title.
In Japan, state broadcaster NHK said that, "If Trump becomes president, Japan along with other countries, are very unsure of what will happen to the economy."
Still, Trump has drawn support from certain global corners, especially right-leaning European leaders, including Britain's Nigel Farage, the former leader of the UK Independence Party, and France's Marine Le Pen, who sent Trump a congratulatory tweet early Wednesday, adding a pat on the back for the "free" American people.
Marine Le Pen's father and founder of the National Front, Jean-Marie Le Pen, took to Twitter to say "long live President Trump!" and claim Trump as part of a worldwide populist wave. "The American people want Donald Trump to be the people's president. Today the United States, tomorrow France. Bravo!" Le Pen wrote.
Far-right leaders in Holland, Belgium, Russia, the Czech Republic, Italy and Serbia, among other places, have also voiced support for Trump. The hard-right Greek party, Golden Dawn, went so far as to make a pro-Trump video starring neo-Nazis.
Immediate reaction from financial markets, however, was brutal. Asian stock markets fell, with Tokyo down almost 6%. The Dow futures markets slid almost 800 points, while the Mexican peso fell to a record low against the US dollar.
But Russians, who followed the election closely, praised the real-estate mogul's victory and called it a positive step for financial markets.
Kirill Dmitriev, head of Russia's sovereign wealth fund, a Russian direct investment fund, said he felt financial market would quickly right themselves.
"We believe that Trump presidency offers more opportunity for global growth and reducing geopolitical confrontations through pragmatic and results oriented approach," Dmitriev said, a position that likely mirrors the Kremlin's. "A less confrontational US foreign policy will unlock major opportunities for joint trade and investment to lead to a more stable and secure world focused on growth and prosperity of its citizens."
The questions raised by the election's unexpected results weren't just financial. Huge unknowns now hover about the future of US alliances around the world, including in Asia. South Korea's National Security Council called an emergency meeting this afternoon to discuss the US election's impact on the country's future plans, the president's office told CNN.
Trump campaigned on a slew of positions that veered sharply away from longstanding pillars of US foreign policy. He has suggested reviewing US support for NATO, and pushing countries like South Korea and Japan to do more for their own defense, including gaining nuclear weapons.
The idea would not only be a repudiation of a decades-long US security umbrella in the region, but flies in the face of previous US efforts to limit the spread of weapons of mass destruction. It also violates a taboo against nuclear weapons in Japan, the only country to be struck by one.
The 70-year-old former reality TV star has suggested he'd upend other international norms during the campaign as well. He said he'd demand allies in Europe and the Middle East do and pay more for their defense, another departure from patterns that have governed US security relationships since World War II.
Trump has proposed closer cooperation with Russia, too, despite ongoing and deepening tensions between Washington and Moscow.
The Trump campaign's ties to Russia, and Moscow's apparent interference in the election in the form of cyberattacks directed solely against Democrats, shadowed the election and raised questions about Russian meddling.
Trump himself has long sought to build international properties in Moscow and has lavished praise on President Vladimir Putin, suggesting that the two would probably get along and cooperate well.
Garry Kasparov, the Russian chess grandmaster and fierce Putin critic, tweeted his reaction to the real-estate mogul's victory: "Winter is here."
The uncertainty about the meaning and impact of a Trump victory was reflected in anxious and sometimes incredulous statements from around the world.
Andres Manuel Lopez Obrador, a former Mexican presidential candidate, called on Mexicans to keep calm. Mexico "is a free, independent, sovereign country. It is not a colony, it is not a protectorate, it does not depend on any foreign government," he said in a video published on his Facebook page Tuesday night.
Trump has accused Mexico of sending rapists to the US and China of stealing jobs from it. He exulted about the profits his hotels would reap when the Brexit vote crashed the UK economy.
He boasted on the campaign trail that he knew more than US military generals and said often that his goal was to be unpredictable -- not usually a sought-after approach among leaders in a nuclear-armed world with live conflicts in the Middle East and Southeast Asia.
The French newspaper Liberation wrote of Trump's projected win in connection to pot legalization also approved in several state referendums Tuesday. The headline read, "US elections: At least now they can use marijuana."
And in Britain, one of the more unvarnished global reactions came from a London fashion magazine. The cover, which hit the streets Tuesday as Americans went to the polls, featured a photo of the United States' newly minted president-elect and a one-word caption: "SH?T."