• colonialism.
• Edward Wadie Said (November 1, 1935–September 24, 2003) was an important public intellectual who applied the critical theories of Foucault, Gramsci, and other postmodernists to post-colonialism and was a strong advocate for the Palestinians in their conflicts with Israel. His most influential work, Orientalism (1978), is primarily concerned with how colonizing cultures frame their portrayals of the colonized.
• Gayatri Chakravorty Spivak (born February 24, 1942) is an Indian scholar whose best known work is "Can the Subaltern Speak?". Influenced by Derrida, Spivak argues that the voice of the subaltern is repressed by the phallologocentric structure of the colonizers language and conceptual categories.

Postcolonialism is a critical theory prominently utilized in literature. Throughout history, the most accepted literary canon existed through the perspective of European imperialism. In writing about imperialism, Europeans demonstrated their belief that the introduction of European culture—and specifically the introduction of the Christian religion—led to the advancement of societies. The cultures and civilizations colonized by the Europeans were viewed as inherently unadvanced, so the Europeans believed that they were morally correct in their imperialism. This sentiment was prominent in literature which often included unfair stereotypes of the native peoples.

As such, this critical theory is heavily tied to postmodernism and has advanced offshoots of the theory, like feminism.

As a response to the canon of literature, there was a rise in writings from the native cultures. The themes in these pieces of literature often center around the social and political power dynamics present in imperialism. Narratives often examine the idea of the colonizer and the colonized as native peoples try to hold on to their cultural and historical traditions and identities in the face of a massive force attempting to revise and change those traditions. There is an inherent distrust of the colonizer as the colonized grapple with the colonizer's attempt to change their culture.

Postcolonialsim began to emerge fully in the late 1960s as a response to white European and American versions of the story of colonialism. White Europeans saw the world through their own cultural lenses and often accepted unquestioningly ideologies that described colonialism as highly beneficial to native peoples because it brought them Christianity and a more "advanced" civilization. White writers often accepted racist teachings and stereotypes about these other cultures that defined them as inferior. When whites went abroad, they then "saw" what they had been taught to see, and further perpetrated these stereotypes to a broad audience. One prominent example of the dominance of the white point of view was Rudyard Kipling. In his poem "The White Man's Burden," he articulated the common overlord opinion that imperialism was a sacrifice noble whites made for the the sake of childlike, ungrateful, and sullen natives, who did not appreciate the benefits they were being offered.

In the latter half of the twentieth century, the muted pushback against writers like Kipling gained steam and grew louder. More and more natives people from former colonies began to publish their own versions of the story of colonization and forced assimilation into European cultural norms. This body of literature was called "postcolonial" and was identified strongly with "the view from below" of oppressed peoples. The formerly colonized usually had a much different story to tell than the whites and were much more critical of the "benefits" they had received from their overlords.

A famous scholar who helped put postcolonial theory on the map was Edward Said, a Middle Eastern man who demonstrated convincingly in his groundbreaking 1978 book Orientalism how whites had lumped disparate cultures together under one "moniker"—the "Orient"—which was largely a fictional construct that enabled the West to justify the enormous power it wielded by stereotyping people from China to Egypt as childlike, irrational, weak, and in need of control. Since the rise of postcolonialism, it has become commonplace to allow native people to tell their own stories in their own voices.

Given the wide nature of the question, I think that there might be some openness to the answer being sought.  In my mind, one of the strongest elements of note in Postcolonialism would have to involve the relationship between the individual, their social order, and the previous imposition of another social structure.  This tripartite relationship lies at the heart of Postcolonial literary theory and the literature that emerges from the genre.  The Postcolonial writer is concerned with how the different prisms through which reality is viewed can help to constitute reality and what is understood by it.  I think that this is probably where Postcolonialism is vitally important for it casts individuals into a setting where different valences of being is examined.  Issues like identity of self in a current context, identity of self in a previous context, and how the modern individual might end up being straddled in one or both worlds simultaneously is vitally important.  For individuals of the Postcolonial time period and for nations that have emerged from the centuries old notion of Colonial identity, these issues are essential for they constitute some of the very basic notions of reality.  I think that any discussion of Postcolonialism has to focus on these points and makes the literary theory and the style of work worthy of note.

Postcolonial literature, which includes literary criticism, is any literature that depicts or interprets colonialism and imperialism from the point of view of the colonized. It is also characterized as the view-from-below or the subaltern view.

For too long, many contend, the story of colonized, displaced, or oppressed peoples was told from the point of view of the conqueror. Notorious examples are Rudyard Kipling's poem "The White Man's Burden," which praises white colonizers for all they put up with trying to "civilize" ungrateful "savages" and the genre of "happy plantation" literature, including Gone with the Wind, that portrays black people as contented and joyful in slavery.

Post-colonial literature tells a far different story. Most often, it is written by a member of a colonized or subaltern group. Writers with knowledge of what it is like to be colonized or oppressed, such as Chinua Achebe, or, in the non-fiction world, Franz Fanon or Edward Said, often can give an authentic and corrective view of what that experience feels like and how it has been misconstrued by the ruling classes.

Post-colonial critics take the perspective of the oppressed and colonized in works of literature. Many critics, for example, have come to the defense of Shakespeare's Caliban in The Tempest, who teaches Prospero how to survive and then is enslaved by him and called a monster.

As the term indicates, the idea of postcolonial literature is reflective of life after colonial rule in nations that were controlled by parent nations.  The idea of how life and identity is constructed after colonialism is rich with ideas, and is a basic element of postcolonial literature.  The genre seeks to examine how the past influences the present and the future, or, in a more postmodern sense, how there is not such a clear distinction of time.  The issues of racial identity plays a large role in postcolonial literature.  At the same time, postcolonial literature seeks to assess how the identity of nations that are controlled and how the identity of people in colonized nations could parallel one another.  At the same time, postcolonial literature is intensely constructed on the idea of what constitutes purity in one's identity.  For example, in postcolonial literature, the idea of how much of one's national or individual identity is contingent on the parent nation or the freed one is extremely important to the genre.

Colonialism is the act of taking partial or total political control over another country through the establishment of a colony or colonies and then exploiting said country for its resources, including labor and economics. The prevailing justifications for colonialism were the moral, intellectual, and religious superiority of the colonizers. Nearly every major first world country has at one time been a colonial power. The colonial era has continued even into the 21st century, although in an attenuated way.

As the Latin prefix intimates then, post-colonialism is the time after the colonial power has been removed or destabilized to the point of inefficacy, and post-colonial literature is that which has been written during or about this time. It is also writing that has been ‘affected by the imperial process from the moment of colonization to the present day’ (Ashcroft, Griffiths, Tiffin, 1989, p. 2). Post-colonial literature is almost always written from the perspective or includes the perspective of the colonized ‘subaltern’ and so attempts to respond to the experience of being colonized. It is often characterized by attempts to re-establish cultural, social, intellectual, political, and linguistic autonomy, a difficult task given that so much of the subalterns’ identity is molded and influenced by their colonizers.

Post-colonial literature has given rise to post-colonial studies, including theory and linguistics foci that study these literatures produced by writers from countries that were once colonized by European powers. By far, post-colonial literature from India is the most abundant, although narrative voices from colonized peoples in Africa are beginning to assert themselves. Trailing, but heard, are voices from America’s native peoples, as well.

Post-colonial criticism is an attempt to reveal the story of oppressed people from their own point of view by correcting or critiquing the perspective of the powerful. It is often called the view from below. For centuries, the story of colonialism was told almost entirely from the perspective of the victorious colonizing culture. Thus, Shakespeare's Caliban is depicted as a monster, a brute, and a savage because he looks different, dares to desire a European woman, and resents obeying his new overlord. But if we look at the story from his point of view, he generously came to the aid of helpless shipwrecked people who would have died without him, only to have them use what he taught them to enslave him, treat him with disdain, and steal his land. Likewise, Kipling's concept of the colonized person as the "white man's burden" is a particularly notorious example of a white colonizer, in this case England, brutally invading and subjecting a land and then casting themselves as sacrificial heroes for imposing their will upon people who would love nothing better than for them to go away. Because the narrative of the powerful is often blind to how life looks and feels to the powerless, it has been important to critique how the literature of a dominant group depicts the people below it. 

The colonial era had a significant cultural influence. Many countries colonized many areas. In particular, England was a great colonial power and colonized locations in the Americas, India, and Africa. What post-colonial literary criticism does is analyze literature written both by colonial powers and by those who were colonized in order to look at the cultural impact of colonization. Now that colonialism is a thing of the past, literary critics are especially interested in analyzing colonial literature to see how the colonial power influenced the colonized in terms of "issues of power, economics, politics, religion, and culture" (Purdue OWL: "Post Colonial Criticism"). They are especially interested to see how the colonial powers interpret the culture of the colonized, how the power views the oppressed.
One example can be seen in the post-colonial interpretation of Joseph Conrad's Heart of Darkness. Western literary critics have viewed the novel as a criticism of colonialism, especially the mother country's treatment of the colonized. However, post-colonialists see Conrad as portraying the colonized Africans as savages in comparison to Europeans and further saying that the Europeans are really just as savage as the Africans. Hence, even though Conrad may have written the book with an anti-colonialist argument in mind, post-colonial critics see him as portraying the oppressed as a savage culture, which reflects the cultural influence of colonization.