In the first gay Pride parade since Ireland became the first country in the world to vote for same-sex marriage, tens of thousands of revelers created a carnival atmosphere on the streets of Dublin on Saturday.
The march was led by a float with a banner that read, "the future is equal", while participants waved rainbow flags under the overcast Dublin sky.
Others carried posters saying "Thank You" and "Yes", a reference to the historic referendum on May 22.
The parade was given added significance after the US Supreme Court ruled Friday that gay marriage is a legal right in all 50 states.
Ireland, a traditionally Catholic nation, voted 62.1% in favor of allowing marriage between two people "without distinction as to their sex", the first time anywhere that gay marriage has been legalized in a referendum.
"This year in particular we have so much to celebrate with the marriage referendum," said Jason Flynn, chairman of Dublin Pride.
"Pride this year will be a way of acknowledging that and sending out a 'thank you' to people for voting Yes."
He added: "We're not 'the other' anymore. It's no longer 'them and us'. We're fully part of society."
Organizers were expecting a record 60,000 people to participate in the parade, the centre-piece of the ten-day Pride festival.
"There's a real celebratory mood this year because of the historic events of last month and yesterday in the US," said Robert Kirwan, 30.
Marqa Kiewied, 33, who moved to Dublin from the Netherlands six years ago, said this was the most "special" Pride she has ever attended.
"It's kind of like it doesn't matter where you're from, who you are, you can just be yourself -- and it's great," she said.
Senator David Norris, Ireland's most renowned gay rights activist, said Pride had come along way since he first attended a march in Dublin in 1974.
"The first march I was in there were eight of us, there's about 80,000 today, which is quite extraordinary," he said at Merrion Square Park, where the parade concluded.
He said the US Supreme Court ruling was a very significant development.
"The Western world is moving in the direction of gay rights in a very substantial way, but of course the rest of the world is going the opposite direction and we have to remember that," he said.
Colorful gay pride parades also took place in other cities across Europe on Saturday.
Several hundred thousand people filled the streets of Berlin, bringing a riot of color to a grey day with many demonstrators in costume -- including US embassy staffer Tim Standaert, who painted his torso blue with an enormous red heart as he waved a rainbow-hued Stars and Stripes flag.
In a sun-drenched Paris, a festive march drew tens of thousands, including the French capital's mayor Anne Hidalgo.
A similar number also marked the annual event in the Italian cities of Milan, Turin and Palermo, where participants used the opportunity to call for same-sex marriage rights, a week after huge crowds demonstrated in Rome against gay unions.