Oluwamayola Ajayi, 31, of Sherman Gardens, Chadwell Heath, used dating website Match.com to ensnare four women using different names and identities.
In one case he sent email threats, purportedly from a captor, saying he had been kidnapped and demanding a ransom.
Ajayi was convicted of conspiracy to defraud after a trial and faces sentence later this week.
Snaresbrook Crown Court heard how Ajayi, who was nominated best international act at the 2011 Gospel Music Awards, gained the women’s trust before persuading them to hand over their savings to fund business enterprises
He insisted the cash would be repaid.
His victims, who all live in America and Canada, were “completely taken in” by his elaborate lies.
They were left humiliated and some were financially ruined by the scam, which ran between November 2009 and August 2010.
One victim handed over more than $125,000 (£78,662) from her late husband’s life savings and dead mother’s estate, which she had earmarked for retirement.
Another disabled woman from Nova Scotia was duped into giving Ajayi almost $38,000 (£23,913) after he pretended to be Travis David McFly, a United States Airforce pilot serving in Iraq.
Ajayi, who was arrested last August at the home he shares with his wife, denied conspiracy to defraud, fraud, concealing criminal property, using criminal property and two counts of possessing articles for use in frauds.
He was unanimously convicted by a jury on all counts after the trial after admitting a single count of possessing a false identity document with intent.
Adjourning sentence, Judge Sarah Paneth told Ajayi he was facing a ‘lengthy’ prison term.