The image of Trump in front of a line of American flags at the convention dominated European newspapers' front pages on Friday with a mixture of reactions to the Republican candidate's manifesto and musings on what the world might look like if he became president of the world's most powerful nation.

Trump's speech focused on the "threat" to the U.S. posed by terrorism, immigration and what he called "unfair" trade deals. In addition, he said that he was the only man who could challenge the elite and "fix" the country. His was a campaign for "Americanism" not "globalism," he added.

Giving his keynote speech at the Republican National Convention on Thursday night, Trump attacked his rival Democrat candidate Hillary Clinton and reiterated his pledges to make America both "safe" and "great" again.

Donald Trump might have whipped the crowds into a frenzy with his first speech as the Republican candidate for the U.S. presidency, but Europe looked on with a mixture of criticism, fear and bemusement.

Republican presidential candidate Donald Trump gives two thumbs up to the crowd during the evening session on the fourth day of the Republican National Convention on July 21, 2016 at the Quicken Loans Arena in Cleveland, Ohio.

In London, the left-leaning Guardian newspaper said in its lead that the Republican had struck an "authoritarian tone in [a] convention speech focusing on recent terrorist attacks and police killings to assure Americans' safety will be restored." The right-leaning Telegraph noted that Trump had promised Americans to be the "law and order candidate" and had, in the process, painted what one journalist called a "dark and terrifying" portrait of America.

Capping a four-day convention in Cleveland, the billionaire businessman and reality TV star said he "humbly and gratefully" accepted the Republican presidential nomination.

Europe's most powerful nation was not too impressed, with newspapers in Germany generally noting that there was little humility in the one hour and 16 minutes Trump addressed the convention making it the longest speech in 44 years.

Der Spiegel noted that Trump's keynote speech was characterized by "attacks against Hillary Clinton and illegal immigrants, many promises and lots of self-praise."

Business daily Handelsblatt's headline focused on Trump's call that "we cannot be so politically correct."

Trump was no less controversial when he promised to clamp down on immigration, strengthen borders and champion hard-working Americans. "I am your voice," he said.

The convention audience cheered wildly as Trump stood in front of a row of American flags to deliver his speech. Chanting "U-S-A, U-S-A," "Lock her up" (referring to Hillary Clinton's recent use of a private email account when she was secretary of state) and "Build the wall!" – a reference to the wall that Trump has promised to build on the U.S.- Mexico border.

Trump has the ability to make even Europe's right-wing political establishment look liberal. The U.K. Independence Party's former leader Nigel Farage, also not known for political correctness, once told CNBC that Trump was "wrong" to call for a complete ban on Muslims entering the U.S.

So it was on Friday, with even Europe's conservative press critical of Trump's key messages. Germany's center-right, conservative Die Welt newspaper noted that Trump's message was "apocalyptic" and "bleak": "The speech was populist through and through and offered no solutions," the newspaper said, adding that it lacked "elegance, humor, self-irony."

France's Les Echos, a right-leaning financial newspaper, said Trump had posed as the "savior of a country at the edge of the Apocalypse" in his "endless" speech on "endangered America." The left-wing Le Monde newspaper also drew attention to Trump's attempt to paint the "most distressing picture possible of the U.S." although it feared that Trump now "has just over three months to arrive at 1600 Pennsylvania Avenue in Washington."

Spain's centrist El Pais newspaper said that Trump's speech, although more "orderly" than his more impromptu utterances, was full of "half-truths and manipulated data," whereas Italy's Corriere della Sera attacked Trump's "absolutely groundless accusation that illegal immigrants would destroy America's middle class."

Not every country in Europe cared about Trump's speech — Russian dailies Vedomosti, Kommersant and the English-language Moscow Times, among others, had no reports on Trump's address.

Correction: This story was revised to correct the White House address to 1600.

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