The tale of a solitary black cat forming unlikely comradeships on a journey sparked by a menacing flood broke records by scoring nominations and then the statuette, something no Latvian film had ever competed for.
"Latvia is so proud today," Latvian President Edgars Rinkevics posted on X, lauding the "Flow" team's "phenomenal achievement".
Rinkevics later posted a picture of himself next to a sculpture of the feline protagonist installed in central Riga.
"It's really unbelievable, something just unimaginable... We are really proud," Sandra Dzene, a 28-year-old wedding photographer, told AFP in Riga.
She was among many Latvians who stopped by the sculpture on a chilly Monday morning, taking group pictures and selfies -- someone had even laid flowers on the cat's tail.
The film had already won a Golden Globe in January, and last month around 15,000 Latvians had queued to take selfies with the trophy that has been put on display in the national museum.
"I feel very proud for our country. Of course, I know it maybe isn't a personal accomplishment," said Gustavs Viksne, a 27-year-old, but the success "brings out the Latvian name in the world".
"That's very important to us," Viksne told AFP.
More than 320,000 people in the country of 1.8 million saw "Flow" in cinemas, a turnout that surpassed such global blockbusters as "Avatar" or "Titanic".
It was another record for a film made on a comparatively minuscule budget of $3.6 million, around a quarter of which was financed by Latvia's state National Film Centre.
"Everybody here is happy, not only in the industry," Inga Blese, the centre's head of production, told AFP.
"With this film you experienced such a phenomenon that people who haven't been going to cinema for many years, they've heard about the film and they went to cinema -- and they liked it," Blese said.
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