For two days last month, a vision of canine paradise emerged in the heart of a city regularly pounded by Russian drones and missiles.

Under sunny skies, thousands of dogs of all sizes and shapes reveled at a festival held in a former Soviet-era factory in the city, Kyiv, the Ukrainian capital. They frolicked in sandboxes, splashed in plastic pools and dove into ball pits — all to the backdrop of pop music blaring from loudspeakers.

In tents and disused warehouses, artists sketched dog caricatures, vendors displayed patterned pajamas and hats for pets, and groomers pampered Pomeranians and chow chows with brushes and lotions.

“It’s like a dog community, and it’s very cute,” said Tetiana Andrus, the owner of Cookie, a 9-month-old Biewer terrier who dashed excitedly around her as they wandered through the PesDay festival, named after a Ukrainian word for dog.

The event, which organizers say drew some 13,000 dogs and about the same number of owners, was a vivid illustration of the boom in dog ownership that has swept across Ukraine since Russia’s full-scale invasion in February 2022. Seeking companionship and comfort during difficult times, many people have turned to the pet that might be called a Ukrainian’s best friend.

“Dogs help refocus your attention from something terrifying to something more positive,” Ms. Andrus said. “You think, ‘OK, if the war is not ending tomorrow or in a few months, I want something good to happen,’” she said. “This is when the dog comes in. He always loves you, even if you are sad.”

There is no national data on pet ownership in Ukraine since the war began, but over the past two years, groomers and dog shelters have reported a surge in purchases and adoptions. Mariia Vronska, the founder of Gostomel Shelter, on Kyiv’s outskirts, said 120 dogs were adopted last year — more than in 2020 and 2021 combined before the war broke out.

In Kyiv, the most popular companions seem to be small, fluffy dogs that people cannot resist petting. Bichons frisés and poodles have become ubiquitous on the streets of the capital, trotting confidently past army recruitment posters and military all-terrain vehicles, or lounging next to their owners during yoga classes.

After more than 30 months of war, many dog owners say their pets have become integral members of their families, sharing in the new realities of wartime life. Like their owners, they have been roused at night by air-raid alerts, scared by nearby explosions and have endured widespread blackouts.

Yana Chestnych, the founder of Pesik Co., a dog clothing brand, said she hugged her Italian greyhound during attacks on her hometown, Kharkiv. “It feels easier and warmer together,” she said at her stand at the festival in Kyiv.

Ms. Andrus, 37, a translator, had long resisted buying a dog, despite her 12-year-old daughter’s persistent requests. But after the war broke out, she said she thought a puppy might help her daughter “focus on better things than this violence.”