It was the middle of the day when Omar Diaw, known by his artist name “Chimere” — French for chimera — approached a blank wall off the main thoroughfare in Guinea's capital and started spray painting.

Civilians and police didn’t bat an eye as Diaw's fellow artists unloaded dozens of paint cans onto the roadside.

Graffiti has thrived for years in Diaw’s native Senegal, where the modern urban street art first took off in West Africa. But when he arrived in Guinea's capital, Conakry, in 2018, he said such art was nearly nonexistent.

“It was thought that graffiti was vandalism,” he said.

To win over the public, Diaw took a gentle approach, using graffiti for public awareness campaigns. One of the first he did was to raise awareness about COVID-19 preventive measures.

“We had to seduce the population,” he said.

The port city of Conakry faces rapid urbanization. Diaw’s graffiti has become an undeniable part of its crowded, concrete-heavy landscape.

His larger-than-life images of famous Guinean musicians and African independence leaders now dwarf the overloaded trucks that drive by. Drying laundry hung over the portrait of the West African resistance fighter Samory Toure.

The tag of Diaw’s graffiti collective, Guinea Ghetto Graff, is on murals all over the city.

Graffiti in its modern form emerged in the United States during the 1960s and 1970s.

The art form reached West Africa in 1988 through Dakar, Senegal, where Amadou Lamine Ngom, known by his artist name Docta, became the region’s first graffiti artist.

In Guinea, Conakry’s governor supports much of Diaw’s work and has given him carte blanche to paint wherever he wants.

The bystanders that ignored Diaw when he started were now stopping on the road to admire the work that was taking shape: a portrait of Guinea’s military leader, General Mamadi Doumbouya, who took power in a 2021 coup.