According to Grote's History of Greece, the Athenian gens, in particular, was held together by the following institutions and customs: Not only Grote, but also Niebuhr, Mommsen and all the other historians of classical antiquity, have come to grief over the gens. Though they correctly noted many of its characteristics, they always took it to be a group of families, thus making it impossible for themselves to understand the nature and origin of the gens. Under the gentile constitution, the family was never an organizational unit, and could not be so, for man and wife necessarily belonged to two different gentes. The whole gens was incorporated within the phratry, and the whole phratry within the tribe; but the family belonged half to the gens of the man and half to the gens of the woman. In public law the state also does not recognize the family; up to this day, the family only exists for private law. And yet all our histories have hitherto started from the absurd assumption, which, since the eighteenth century in particular, has become inviolable, that the monogamous single family, which is hardly older than civilization, is the core around which society and state have gradually crystallized. Morgan prefers to quote Grote because he is not only an impressive but also a trustworthy witness. Grote goes on to say that every Athenian gens had a name derived from its supposed ancestor; that it was the general custom before Solon, and even after Solon, in the absence of a will, for the property of a deceased person to pass to the members of his gens (gennetai), and that in the case of a murder it was the light and the duty, first of the relatives of the murdered man, then of the members of his gens, and lastly of his phratry, to prosecute the criminal before the tribunals: All that we hear of the most ancient Athenian laws is based upon the gentile and phratric divisions. (Grote.) The descent of the gentes from common ancestors has caused the pedantic philistines, as Marx calls them, a lot of brain-racking. As they of course declare the common ancestors to be pure myths, they are at an utter loss to explain how the gens originated out of a number of separate and originally quite unrelated families; yet they have to perform this feat in order to explain how the gentes exist at all. So they argue in circles, with floods of words, never getting any further than the statement: the ancestral tree is a fairy tale, but the gens is a reality. And finally Grote declares (interpolations by Marx): Marx summarizes Morgan's reply to this as follows: As among the Americans, the phratry was a mother gens, split up into several daughter gentes, and uniting them, often tracing them all to a common ancestor. Thus, according to Grote, Hence, all the gentes of this phratry were literally brother gentes. The phratry still occurs in Homer as a military unit in that famous passage where Nestos advises Agamemnon: Draw up people by tribes and by phratries so that phratry may support phratry, and tribe tribe. The phratry has further the right and the duty of prosecuting for blood-guilt incurred against a phrator; hence in earlier times it also had the obligation of blood revenge. Further, it had common shrines and festivals; in fact the elaboration of the whole Greek mythology out of the traditional old Aryan nature-cult was essentially conditioned by the phratries and gentes, and took place within them. The phratry also had a chief (the phratriarchos) and, according to de Coulanges, assemblies. It could pass binding resolutions, and act as a judicial and administrative body. Even the later state, while it ignored the gens, left certain public offices in the hands of the phratry. Several related phratries form a tribe. In Attica there were four tribes, each consisting of three phratries, each phratry numbering thirty gentes. Such a rounded symmetry of groups presupposes conscious, purposeful interference with the naturally developed order. As to how, when, and why this occurred,. Greek history is silent; the historical memory of the Greeks only went back to the heroic age. As the Greeks were crowded together in a relatively small territory, differences of dialect were less developed than in the wide American forests; yet in Greece also it was only tribes of the same main dialect that united in a larger organization, and even Attica, small as it was, had a dialect of its own, which later, through its general use as the language of prose, became the dominant dialect. In the Homeric poems we find most of the Greek tribes already united into small nations, within which, however, gentes, phratries, and tribes retained their full independence. They already lived in towns fortified with walls; the population increased with the increase of the herds, the extension of agriculture and the beginnings of handicraft. The differences in wealth thus became more pronounced, and with them the aristocratic element within the old primitive democracy. The various small nations waged incessant wars for the possession of the best land and doubtless also for booty; the use of prisoners of war as slaves was already a recognized institution. The constitution of these tribes and small nations was as follows: In addition to his military functions, the basileus also held those of priest and judge, the latter not clearly defined, the former exercised in his capacity as supreme representative of the tribe or confederacy of tribes. There is never any mention of civil administrative powers; he seems, however, to be a member of the council ex officio. It is there fore quite correct etymologically to translate basileus as king, since king (kuning) is derived from kuni, kunne, and means head of a gens. But the old Greek basileus does not correspond in any way to the present meaning of the word king. Thucydides expressly refers to the old basileia as patrike, i.e. derived from gentes, and says it had strictly defined, and therefore limited, functions. And Aristotle says that the basileia of the heroic age was a leadership over free men and that the basileus was military leader, judge and high priest; he thus had no governmental power in the later sense.  Thus in the Greek constitution of the heroic age we see the old gentile order as still a living force. But we also see the beginnings of its disintegration: father-right, with transmission of the property to the children, by which accumulation of wealth within the family was favored and the family itself became a power as against the gens; reaction of the inequality of wealth on the constitution by the formation of the first rudiments of hereditary nobility and monarchy; slavery, at first only of prisoners of war, but already preparing the way for the enslavement of fellow-members of the tribe and even of the gens; the old wars between tribe and tribe already degenerating into systematic pillage by land and sea for the acquisition of cattle, slaves and treasure, and becoming a regular source of wealth; in short, riches praised and respected as the highest good and the old gentile order misused to justify the violent seizure of riches. Only one thing was wanting: an institution which not only secured the newly acquired riches of individuals against the communistic traditions of the gentile order, which not only sanctified the private property formerly so little valued, and declared this sanctification to be the highest purpose of all human society; but an institution which set the seal of general social recognition on each new method of acquiring property and thus amassing wealth at continually increasing speed; an institution which perpetuated, not only this growing cleavage of society into classes, but also the right of the possessing class to exploit the non-possessing, and the rule of the former over the latter. And this institution came. The state was invented.
Origins of the Family-- Chapter IV