New Year's Eve violence in the Iraqi capital and an underlying threat of terrorism in the United States, Britain and Israel provided a grim counterpoint to the high spirits greeting 2004.
But Australians celebrated in colorful style with Sydney's famous harbor alight with colorful fireworks. In New Zealand (search), thousands crammed into a public square, dancing and waving glow sticks. Still, a tactical response team scoured the streets of Sydney (search), looking out for everything from drunken revelers to any possible security threat.
Pope John Paul II gave thanks for 2003 and prayed for world peace in 2004 during a vespers service at St. Peter's Basilica (search). His New Year's Mass on Thursday will mark the Roman Catholic Church's World Day of Peace.
In central Baghdad, a car bomb ripped through a restaurant during a New Year's Eve party, killing five Iraqis and injuring 35, including at least two Americans and one Briton.
Celebrations also turned deadly in the Philippine city of Lucena when fireworks started a fire in an old public market, killing at least 14 people.
In Israel, the threat of terrorism prompted even greater security efforts than usual. Police said Wednesday that reinforcements were patrolling night spots in Tel Aviv during celebrations, days after Israeli security officials warned of the possibility of a major New Year's terror attack at a public building or holy site.
The United States took special precautions, banning flights other than scheduled commercial airliners over Manhattan and Las Vegas for several hours during celebrations.
In Paris, about 4,500 police officers and soldiers patrolled the city streets. The police presence was strong around the Champs-Elysees, the famous tree-lined boulevard in western Paris where the crowds gathered. No specific terrorist threat was announced.
The green, pink and red glow of Roman candles lit up the Champs Elysees as roars of delight broke out just at midnight.
Young North Africans holding up the Algerian flag danced atop concrete barriers, a group of Italians posed for pictures, and a young Danish couple bargained with a street vendor for two cans of beer.
"It's great so far," said Ben Jacobs, a U.S. college student from Northville, Mich. who was visiting the city with friends.
London's Metropolitan Police said there was a "high state of alert" but there were no specific terrorist threats for New Year's Eve.
For many in Britain, the weather appeared a more immediate threat to the festivities than terrorism.
The west coast city of Liverpool rescheduled its fireworks display to Friday because of forecasts of sleet, rain and gale force winds.
But in London, the weather held off and thousands enjoyed a brief but spectacular fireworks show at the London Eye. The huge sightseeing wheel at the edge of the River Thames became a necklace of light against the black sky and then exploded with rockets and multicolored fireworks as the crowd cheered.
As in years past, crowds also flocked to Trafalgar Square in central London, despite the fact that no events were planned there.
In Scotland, where New Year's "Hogmany" revels are legendary, Scottish high spirits fought back against driving rain and high winds. But in the end, Edinburgh canceled its events because of the weather and concerns for public safety. About 100,000 people had been expected to gather in the city center for a street party, concert and fireworks.
In Berlin, thousands of New Year's revelers packed a 2-mile-wide area around the Brandenburg Gate, listening to music and watching fireworks.
In Athens, fireworks streaked over the 2,500-year-old Parthenon in New Year celebrations marking the final stage of preparations for the 2004 Olympic Games in August.
Thousands of Athenians of all ages crowded into a central square in front of parliament to watch a light show and performances from Greek and international artists.
In Afghanistan, American soldiers celebrated with karaoke, fireworks and a traditional ball drop before the midnight countdown.
Two-hundred-and-forty miles above the Earth, in the relative comfort of the International Space Station, a U.S.-Russian crew marked New Year's with roast chicken and tea.
U.S. astronaut Michael Foale and his Russian crew mate, Alexander Kaleri, said in a video hookup Wednesday they would toast each other when the clock strikes midnight in London since the station's clock is set to Greenwich Mean Time.
In Japan, Emperor Akihito mourned the losses of Japanese lives last year in tragedies overseas as he prayed for brighter times in the coming year. The emperor's New Year's address comes as Japanese troops embark to Iraq in their largest and potentially most dangerous overseas deployment since World War II.
Meanwhile, Japanese Prime Minister Junichiro Koizumi kicked off the new year by visiting a controversial shrine honoring Japan's war dead, a decision that is certain to rile countries in Asia that Japan invaded and brutally occupied last century.