History's first sovereign default came in the 4th century BC,committed by 10 Greek municipalities. There was one creditor: thetemple of Delos, Apollo's mythical birthplace.

Twenty-four centuries later, Greece is at the edge of thebiggest sovereign default, and policy makers are worried aboutglobal shock waves of an insolvency by a government with 353billion euros ($483 billion) of debt — five times the size ofArgentina's $95 billion default in 2001.

“There is a monstrously large amount of uncertainty and amassive range of possibilities,” said David Mackie, chief Europeaneconomist at JPMorgan Chase & Co. in London. “A macroeconomicdisaster could be averted but only by aggressive policy action” bycentral banks and governments.