Archbishop Paul Marcinkus, who was involved in one of the biggest financial scandals to hit the Vatican, has died, church officials say.
Marcinkus had been one of the most powerful men in the Church
The 84-year-old American had been living in Sun City, Arizona.
Marcinkus was head of the Vatican Bank at the time of the fraudulent collapse of Banco Ambrosiano in 1982, with which it had close ties.
He denied any wrongdoing. Although he was sought for questioning, he was granted immunity as a Vatican employee.
Archbishop Marcinkus was found dead at his home on Monday evening, a spokeswoman for the Roman Catholic Diocese of Phoenix, in Arizona, said. The cause is unclear.
He retired in 1990, but had remained active in the local ministry.
Born in 1922 in a suburb of Chicago, he was ordained as a priest in 1947 and then as an archbishop in 1969.
An imposing 1.9m (6ft 4in) tall, he acted as a bodyguard to Pope John Paul II during his early foreign travels.
Archbishop Marcinkus was appointed to the Institute for Religious Works, known as the Vatican Bank, in 1971 and worked there until 1989.
The bank was the main shareholder in Banco Ambrosiano.
The head of Banco Ambrosiano, Roberto Calvi, was found hanging under Blackfriars Bridge in London shortly after the bank's collapse with debts of $1.3bn (£750m).
The missing money was traced to loans made to 10 dummy companies in Latin America, and the speculation was that the Mafia were involved.
Five people are currently on trial in Italy for Calvi's murder.