How do culture, policy, and religious beliefs impact the way we view suicide?

Suicide is an act which has been viewed quite differently in different places and times throughout human history. In Western culture, the long-standing attitude toward it has been a negative one. Christian belief generally indicates that those who kill themselves will be punished for it in the afterlife. Yet even in the West, there has been an ambivalence about the act of taking one's own life, depending upon the surrounding circumstances and the context in which the act is occurs or is depicted.
Our understanding of suicide is heavily influenced by not only religion but literature. Although Christianity condemns the act as immoral, many literary works nevertheless depict suicide as a heroic act, and literary and historical figures who kill themselves are often looked up to as admirable. It is true, however, that often such actions, viewed this way, occurred prior to the Christian period. In Virgil's Aeneid, the suicide of Dido has been a cultural trope for 2,000 years and is emblematic of the despairing fate of a rejected woman. If we fast forward 1600 years to the Elizabethan period, we can see that Shakespeare, in his portrayals of events taking place in antiquity, depicts suicide in accord with the ethic of that time. The ancients did not fear being punished in the afterlife for killing themselves. But there is still a huge paradox in the "modern" (that is, post-1500 CE) celebration of that act in Shakespeare and other authors, when performed by figures either ancient or modern. Cleopatra's suicide occurs in pagan antiquity, but Othello's is during the period of Christianity.
It's also true that literature has historically influenced the actions of readers. A seminal work, in this regard, was Goethe's novel The Sorrows of Young Werther (1774). The book was such a sensation that it encouraged young men to emulate Werther's suicide by dressing in the same clothes as Werther is described as wearing before putting a bullet in their brain, as he does. Here, we can see that the weakening of religious belief during the eighteenth-century Enlightenment did result in a change in cultural attitudes about the act. Goethe describes Werther's funeral as one in which no clergyman is in attendance. It is not only that Werther's act, as the response of a hopeless lover, was considered admirable but that his status as a freethinker and his independence from organized religion served as a focal point of the Zeitgeist.
In our time, the issue of assisted suicide is also affected by religious belief or the lack thereof. Conservative politicians in the US who uphold traditional Christian belief also tend to link a number of issues, including abortion, euthanasia, and assisted suicide, together in the category of actions inimical to the sanctity of life they intend to champion. Yet the very fact that assisted suicide is talked about at all as a legitimate option attests, as we've already alluded, to the weaker, less stringent religious beliefs of our time in comparison with the past.
In non-western cultures, of course, suicide is viewed quite differently. In Japan, for instance, it is often explicitly considered a noble act taken in order to preserve a person's honor. Yet it is interesting that given the literary examples cited above, the western and eastern attitudes toward suicide are perhaps not as different as they might seem on the surface.