Parisians welcomed have with a spectacular lights and firework show over the Arc de Triomphe, at the end of the French capital's famous Champs-Elysees avenue.
The display began punctually at midnight, and television pictures showed a huge crowd of people. Several hundred thousand had been expected to attend.
During the lights show the names of the French football team that won the World Cup this year were projected onto the Arc de Triomphe.
As in previous years, following a string of deadly terrorist attacks in France, there were strict security measures in place. "Yellow vest" protesters had also announced a protest for the Champs-Elysees.
However, by just after midnight, celebrations appeared to have passed off peacefully.
In Berlin, tens of thousands of people greeted 2019 at a huge party at Berlin's Brandenburg Gate, the largest New Year's Eve party in Germany.
Festivities culminated with a laser and fireworks display, which followed performances by musical acts including Eagle Eye Cherry and Bonnie Tyler.
Earlier, some 30,000 people in Japan welcomed in the New Year at Saitama Super Arena with Floyd Mayweather.
The American boxer soundly defeated his opponent, Japanese kickboxer Tenshin Nasukawa, in the first round of what was billed as three rounds of entertainment.
And as Russians raised toasts to celebrate across the country's 11 time zones, President Vladimir Putin stressed the need to rely on internal resources to improve living standards.
In a televised address just before midnight, Putin said, "we can achieve positive results only through our own efforts and well co-ordinated teamwork".
Meanwhile, hundreds of Thais travelled to Takien Temple in a suburb of Bangkok to lie inside coffins for traditional funeral rituals.
Participants believe the ceremony - symbolising death and rebirth - helps rid them of bad luck and allows them to be born again for a fresh start in the new year.
They held flowers and incense in their hands as monks covered them with pink sheets and chanted prayers for the dead.
Earlier, the Pacific island nation of Kiribati was the first in the world to welcome the new year, greeting 2019 with muted celebrations after spending 2018 on the front line of the battle against climate change.
The new year was welcomed in the capital, Tarawa, with church services and mostly quiet private celebrations.
In Auckland, tens of thousands gathered around Sky Tower as fireworks exploded from the top of the 328m structure.
Across the country thousands took to beaches and streets, becoming the first major nation to usher in 2019, with fireworks booming and crackling above city centres and harbours.
Thousands of South Koreans filled the streets of Seoul for a traditional bell-tolling ceremony near City Hall.
A "peace bell" was tolled at Imjingak, a pavilion near the border with North Korea.
In New York, Snoop Dogg, Sting and Christina Aguilera will welcome 2019 in a packed Times Square along with revellers from around the world who come to see the traditional crystal ball drop.
Spectators began assembling early in the afternoon for the made-for-TV extravaganza.
The celebration will take place under tight security, with partygoers checked for weapons and then herded into pens, ringed by metal barricades, where they wait for the stroke of midnight.
Australian Associated Press