Student Izabelle Stevens, 20, initially thought the red, white and blue flag erected along her street in British Columbia, Canada, was just a coincidence, and turned the other cheek.
But she later decided to check the man’s social media – and believes the content he shared proves he supports Putin’s war.
After watching the horrific events unfold in Ukraine from the safety of her home, Izabelle felt compelled to take action, Yahoo Australia reports.
She posted videos detailing the suburban spat on TikTok, which has now racked up more than two million views.
Izabelle said the clip also sparked a community effort to stand up against the man’s misguided support.
She told Yahoo: “At first, I could tell that all of the neighbours in my area were really shocked, but none of us really did anything.
“We were trying to keep the peace and trying be positive.
“It’s kind of like a Canadian thing, where you don’t really want to start problems with your neighbour and you want to be kind.”
Izabelle said she decided to take a stand when she saw a visiting maintenance worker become visibly upset by the flag.
She felt that her neighbour displaying the flag was seen to be representing the whole street.
In a video posted on TikTok in early April, Izabelle says the “only reasonable” response was to fly Ukrainian flag.
In just a few days, Izabelle said she noticed other neighbours erecting flagpoles and hoisting the same blue and yellow flag.
She said one of her neighbours, who was on holiday in Mexico at the time, texted another neighbour asking them to take down the Canadian flag in exchange for a Ukrainian one.
Izabelle said: “So then we slowly started surrounding him (with Ukrainian flags).”
In an unsettling escalation, the Russia -supporting neighbour then erected a 20ft-high flagpole flying an obscure red and yellow flag which she said was associated with a Russian far-right hate group.
Izabelle said she confronted the neighbour about the flag, but he said he didn’t know its meaning and removed it.
The 20-year-old said the social media attention has led to the road becoming a tourist spot, with people coming to the area just to view the flags.