The book argues that the pattern is sharply evident, for example in the 300 years of Ancient Greek history, the Swiss cantons since the 14th century, the County of Flanders during the 14th century, the three-and-a-half centuries of the Hanseatic League, and Renaissance Italy. Those periods included numerous societies that frequently changed types of regime. Those societies abruptly stopped fighting other oligarchies if they became oligarchies and abruptly stopped fighting other democracies if they became a democracies. That pattern immediately reversed if the regime type changed again.