Koskotas was born in Greece on October 5, 1954. He migrated to the US with his parents in 1970. Koskotas grew up in the United States, returned to Greece in 1979 and joined the Bank of Crete as an accountant. He bought the Bank of Crete in 1984 and then built a banking and publishing empire that controlled three daily newspapers, a radio station and the soccer team Olympiakos of Piraeus. Later, he was incarcerated on an embezzlement conviction after a shortfall of 132 million dollars was discovered in the bank.
In the months that followed, Koskotas, who had by then fled to the United States, claimed that the late prime minister and PASOK party founder Andreas Papandreou ordered state companies to deposit funds with the bank, and took bribes from stolen money. The allegations resulted in the resignations of several ministers and demands for a vote of no confidence in the government. Mr. Papandreou, who died in 1996, was cleared of all charges by a special court in 1992 and was re-elected in 1993.
He was paroled and released from prison on March 16, 2001. He had served 12 years of a 25-year sentence for embezzlement, forgery and obstruction of justice felonies. Barred from leaving the country, Koskotas had also been ordered to report to an Athens police precinct twice a month.