Walter Schiedel and Steven Friesen, two historians of the Roman Empire, have recently attempted to estimate wealth inequality in the Roman Empire when it was at its zenith using papyri ledgers, previous scholarly estimates, imperial edicts, and Biblical passages. Schiedel and Friesen estimate that in 150 AD, the top 1% of Roman society controlled 16% of the wealth, less than half of what America’s top 1% control today! It is also much lower than wealth concentration in N. Ireland - according to the estimate in my recent OEP article, the top 1% of population back in 2001 controlled 22% of the wealth. I have no doubt that that figure is much higher for 2011. You can read more about Schiedel and Friesen's work here.
As an undergraduate, I was taught about the failure of Herstatt Bank in 1974 and Herstatt risk. This bank was only the 35th largest bank in Germany at the time so why would anyone be interested in studying its failure? Herstatt failed because of its involvement in risky foreign exchange business. When it closed its doors on 26 June 1974, counterparty banks (mainly in New York) had not received dollars due to them because of time-zone differences - this is known as settlement risk. The cross-jurisdictional implications of its failure resulted in the Bank for International Settlements setting up the Basel Committee on Banking Supervision and Herstatt's failure was a key reason for the establishment of real-time gross settlements systems, which ensures that payments between two banks are executed in real time. The Bank of England's Ben Norman has an interesting post on Herstatt over at the Bank's new blog ( Bank Underground ). As well as giving an excellent overview of