And the United Nations Educational, Scientific, and Cultural Organization named him UNESCO Artist for Peace in 2005.
Nigerian newspapers gave variations on his birth name, but the Nigerian website Next reported that he was "christened Olaniyi Osuntoki" and took the Seven-Seven name "because he was the lone survivor of seven sets of twins."
The UNESCO website stated that his art had been in exhibitions "throughout the world," including the National Museum of Modern Art in Paris, the Contemporary Arts Museum Houston, the Museum of Modern Art in New York, the National Museum of African Art in Washington, and the National Modern Art Gallery in Lagos, Nigeria.
UNESCO called him "the most famous representative of the renowned Oshogbo school of painting, which is at the heart of Yoruba civilization" - one of the three major ethnic groups in Nigeria.
The UNESCO appreciation stated that "his work reflects the cosmology and mythology of Yoruba culture, depicting a fantastic universe of human figures, animals, divinities, and plants. His varied style, using different techniques and astonishing materials, is the most copied in contemporary Nigeria art."
He also was "a singer, musician, actor, writer, and poet," UNESCO stated.
A February 2010 story on the Next website stated that before taking up art, he had been "a street dancer for a medicine seller" and then a bandleader.
Anthony Fisher, who showed his work at the Indigo Arts Gallery in Philadelphia in 1995, wrote in an e-mail that "between political troubles and personal setbacks in his home country, Twins spent much of the last 20 years abroad. . . .
"Philadelphia became his refuge and second home."
From 1997 to 1999 and from 2004 to 2007, he rented a house in Darby, and at other times stayed with Nigerian friends in Southwest Philadelphia, wrote Harriet Schiffer of Jenkintown, who maintains the website www.asanteculturalheritage.com, in an e-mail.
Biographer Glassie wrote that, when he returned in 2000, "beaten down by repetitive failures, he drifted toward despair."
In an earlier stay in Philadelphia, "he had been hired as the security guard of the parking lot . . . then fired for sleeping on the job" at Material Culture, in a former railroad train garage at Roberts and Wissahickon Avenues.
Then, in the early 2000s, he began "decorating old Turkish pots, painting pictures on brown paper bags that Material Culture gave to good customers."
When owner George Jevremovic told Glassie "that he had hired a mercurial character named Twins Seven-Seven," the biographer wrote, "I was shocked.
"How could this man be down and out in Philly?
"I had admired his work since the early [1970s], when colleagues and friends who were experts in African art . . . told me about a young artist who was reshaping the Yoruba tradition into modern masterpieces."
But when coworkers "groused" about his irregular appearances, the biographer wrote, the firm "cleared out a small, well-lit room by the carpenters' shop, allowing him to come and go at will. . . .
"It marked the beginning of a fresh and hopeful phase in Prince's turbulent life."
In a phone interview, Jevremovic confirmed Glassie's account in the biography, published jointly by Material Culture and Indiana University Press.
Survivors include several children and former wives in several cities, Fisher and Schiffer said. No local services are planned.
Contact staff writer Walter F. Naedele at 215-854-5607 or wnaedele@phillynews.com.
