View source for '''Friedrich Engels''', Origins of the Family, Private Property and the State

Extracts from Engels "The Origin of the Family, Private Property and the State", 1884. 

"According to the materialistic conception, the determining factor in history is, in the final instance, the production and reproduction of the immediate essentials of life. This, again, is of a twofold character. On the one side, the production of the means of existence, of articles of food and clothing, dwellings, and of the tools necessary for that production; on the other side, the production of human beings themselves, the propagation of the species. The social organization under which the people of a particular historical epoch and a particular country live is determined by both kinds of production: by the stage of development of labor on the one hand and of the family on the other."

Preface to the First Edition, 1884

"Thus when monogamous marriage first makes its appearance in history, it is not as the reconciliation of man and woman, still less as the highest form of such a reconciliation. Quite the contrary. Monogamous marriage comes on the scene as the subjugation of the one sex by the other; it announces a struggle between the sexes unknown throughout the whole previous prehistoric period. In an old unpublished manuscript, written by Marx and myself in 1846, [The reference here is to the German Ideology, published after Engels’ death – Ed.] I find the words: “The first division of labor is that between man and woman for the propagation of children.” And today I can add: The first class opposition that appears in history coincides with the development of the antagonism between man and woman in monogamous marriage, and the first class oppression coincides with that of the female sex by the male."

II. The Family, 4. The Monogamous Family

"The modern individual family is founded on the open or concealed domestic slavery of the wife, and modern society is a mass composed of these individual families as its molecules. In the great majority of cases today, at least in the possessing classes, the husband is obliged to earn a living and support his family, and that in itself gives him a position of supremacy, without any need for special legal titles and privileges. Within the family he is the bourgeois and the wife represents the proletariat."

Idem. 

[http://www.marxists.org/archive/marx/works/1884/origin-family/preface.htm Preface to the first edition, 1884]