Socialism

Capital, Volume 1 was first published in 1867, when capitalism was dominant in western Europe and it was both dramatically improving production while pushing down the quality of life of the proletariat. Capital is a critique of "Political Economy," the common bourgeois justification for capitalism. Marx's chief observation about capitalism that enables socialism is capitalism's centralizing tendencies, which increases the ratio of proletarian to bourgeois, while also training the proletariat on how to run and administer a complex and centralized economy.

The old, tribal formations were not socialist, they had no socialized production. It was cooperative, but extremely small-scale. Feudalism did not pave the way for socialism, either, but instead gave birth to capitalism. Capitalism's centralization and introduction of large, industrial production does give way to a large, single class that can collectively run and plan production, ie socialism. From Manifesto of the Communist Party:

The essential conditions for the existence and for the sway of the bourgeois class is the formation and augmentation of capital; the condition for capital is wage-labour. Wage-labour rests exclusively on competition between the labourers. The advance of industry, whose involuntary promoter is the bourgeoisie, replaces the isolation of the labourers, due to competition, by the revolutionary combination, due to association. The development of Modern Industry, therefore, cuts from under its feet the very foundation on which the bourgeoisie produces and appropriates products. What the bourgeoisie therefore produces, above all, are its own grave-diggers. Its fall and the victory of the proletariat are equally inevitable.

Communism has not stopped blooming. Or, rather, it hasn't started, either. Communism is a future system of fully collectivized, classless production. Socialism is still thriving, of course, it's the form of economy of the PRC, Cuba, Vietnam, etc.

Tell me, what should I read of Marx that goes against the theory of historical materialism and scientific socialism?

We shall, of course, not take the trouble to enlighten our wise philosophers by explaining to them that the “liberation” of man is not advanced a single step by reducing philosophy, theology, substance and all the trash to “self-consciousness” and by liberating man from the domination of these phrases, which have never held him in thrall. Nor will we explain to them that it is only possible to achieve real liberation in the real world and by employing real means, that slavery cannot be abolished without the steam-engine and the mule and spinning-jenny, serfdom cannot be abolished without improved agriculture, and that, in general, people cannot be liberated as long as they are unable to obtain food and drink, housing and clothing in adequate quality and quantity. “Liberation” is an historical and not a mental act, and it is brought about by historical conditions, the development of industry, commerce, agriculture, the conditions of intercourse...

• Karl Marx, The German Ideology

One more, for good measure, from Draft of a Communist Confession of Faith:

Question 13: Then you do not believe that community of property has been possible at any time?

Answer: No. Communism has only arisen since machinery and other inventions made it possible to hold out the prospect of an all-sided development, a happy existence, for all members of society. Communism is the theory of a liberation which was not possible for the slaves, the serfs, or the handicraftsmen, but only for the proletarians and hence it belongs of necessity to the 19th century and was not possible in any earlier period.