In general, unism, as a consistent ideology, must accumulate the ideas appearing in the human culture over millennia. Any portion of philosophy that carries the idea of uniqueness, universality and unity of the world can be said to belong to unism as its integral component. Still, there are philosophies that express that kind of ideas in the most clear and unambiguous manner. G. W. F. Hegel and Karl Marx can be called the nearest philosophical predecessors of unism: the former invented a consistent method for treating universality in philosophy; the latter demonstrated how this method should be used in a consistent way. In unism, one can trace the influences of Ancient Greek philosophy, the French philosophers of the Renaissance and the Early Enlightenment (Pierre Gassendi, Dom Deschamps), and, of course, Baruch Spinoza. There is also a definite mark of the Indian and Chinese teachings, especially their materialistic flavors.
Most modern philosophies fail to achieve the level of integrity charactering earlier teachings. In the XX century, the fundamental problem of the unity of the world has been reduced to mere reductionism, or even entirely dismissed. As a result, new philosophies either unreasonably extended the range of applicability of special methodological principles, or substituted inconsistent, sparse, chaotic, politically engaged verbiage for philosophical thought. A number of new ideas have been proposed in the former USSR, within its official (and very restricted) sort of Marxism, but, in general, modern philosophy is still rather stagnant; that is why it did not contribute much into the development of unism. In the end of the XX century, philosophers began to rediscover the ideas of dialectical and historical materialism, still diluting them in conceptual confusion and pseudo-scientific talk.
Science has certainly been one of the basic sources of inspiration for unism. The history of science provides an excellent example of hierarchical development, and the hierarchy of science was a ready model for hierarchies in general. In most cases, however, science contributed to unism in a negative way: the attempts to formalize the idea of hierarchy have lead to a clear understanding that such a formalization cannot be achieved without a drastic revision of the very logic of formalization, and the principles of hierarchical logic have been formulated as a result of the search for the limits of scientific research. No "meta-science" could be universal enough to become philosophy, and the need for a wider basis for unism became evident.
In particular, studies in formal logic and mathematics were very important for developing the logic of unism, the hierarchy of classical, dialectical and diathetical logic. Considering the foundations of mathematics and the numerous "alternative" and "nonstandard" theories, one comes to the idea of the hierarchical nature of formal truth and the necessity of a greater attention to the limits of logical and mathematical reasoning.
Interest to human psychology was one of the major sources of unism, since nowhere else the universal reflexivity of hierarchical development manifests itself with a comparable clarity. Primarily, the psychology of art perception and psychological aspects of creativity were in the spotlight; later, most branches of modern psychology and even some aspects of psychiatry were involved. The formation of consciousness in the course of natural development has always been a central problem in the philosophy of unism.
Computer technology has much influenced the formation of unism as well. The history of ideas, hardware and software architecture, networking protocols and distributed computer applications give yet another model of the fundamental processes of development treated in unism. The rapid technological progress in computing makes them easier to observe. Also, computers seem to provide a universal simulation tool; they suggest active acquisition instead of mere contemplation.
And, of course, unism would be impossible without applications in the arts. Art is very diverse and dynamic; it allows quick implementation of any general idea, albeit in a syncretic way, which may hinder clear perception of the underlying principles.