Yet there was always a certain tradition of unity between all the Greeks, based on a common language and script, on the common possession of the heroic epics, and on the continuous intercourse that the maritime position of the states made possible. And, in addition, there were certain religious bonds of a unifying kind. Certain shrines, the shrines of the god Apollo in the island of Delos and at Delphi, for example, were sustained not by single states, but by leagues of states or Amphictyonies (= League of neighbours), which in such instances as the Delphic amphictyony became very wide-reaching unions. The league protected the shrine and the safety of pilgrims, kept up the roads leading thereunto, secured peace at the time of special festivals, upheld certain rules to mitigate the usages of war among its members, and--the Delian league especially--suppressed piracy. A still more important link of Hellenic union was the Olympian games that were held every four years at Olympia. Foot races, boxing, wrestling, javelin throwing, quoit throwing, jumping, and chariot and horse racing were the chief sports, and a record of victors and distinguished visitors was kept. From the year 776 B.C. onward[177] these games were held regularly for over a thousand years, and they did much to maintain that sense of a common Greek life (pan-Hellenic) transcending the narrow politics of the city states. Such links of sentiment and association were of little avail against the intense “separatism” of the Greek political institutions. From the History of Herodotus the student will be able to gather a sense of the intensity and persistence of the feuds that kept the Greek world in a state of chronic warfare. In the old days (say, to the sixth century B.C.) fairly large families prevailed in Greece, and something of the old Aryan great household system (see Chap. XV), with its strong clan feeling and its capacity for maintaining an enduring feud, still remained. The history of Athens circles for many years about the feud of two great families, the Alcmæonidæ and the Peisistratidæ; the latter equally an aristocratic family, but founding its power on the support of the poorer class of the populace and the exploitation of their grievances. Later on, in the sixth and fifth centuries, a limitation of births and a shrinkage of families to two or three members--a process Aristotle notes without perceiving its cause--led to the disappearance of the old aristocratic clans, and the later wars were due rather to trade disputes and grievances caused and stirred up by individual adventurers than to family vendettas.