how does the caste system factor into enlightenment of buddha
After Buddha’s death, his followers had different ideas on how to interpret his teachings. These differences led to many different forms of Buddhism. The three main forms that still exist today are Theravada, or “the lesser vehicle,” Mahayana, or “the greater vehicle,” and Vajrayana, or “the diamond vehicle.” Each form more or less follows the original ideas of Buddha and the four noble truths, with slight variations in each form. For example, followers of Theravada Buddhism believe that anyone can attain enlightenment, while Mahayana Buddhism maintains that enlightenment can only be attained with the help of an experienced teacher (Jansen, p. 14). Despite the differences, all Buddhists believe in the idea of enlightenment through the eightfold path, which eventually leads to nirvana, or freedom from the cycle of rebirths, a concept also important to Hinduism.
Bulliet, R. (2001). The earth and its peoples(2 nd edition). New York: Houghton Mifflin Company.
Although the majority of the country’s population is Buddhist today, animism continues to influence Cambodia and its religion. Most Cambodian Buddhists still believe in spirits and most houses have a shrine, that they often build themselves.
Because Buddhism comes from Hinduism, the two religions have many similarities. Firstly, both religions believe strongly in reincarnation and that this endless cycle of rebirths and deaths needs to be broken to find peace. Both religions also believe that meditation is very important and that spirituality is found inward instead of outward. Lastly, both believe that eventually, everything on earth will achieve freedom through enlightenment.
The Jataka stories (one Pali collection contains 547 of them) have remained among the most popular forms of Buddhist literature. They are the source of some 32 stone carvings at the 2nd-century bce stupa at Bharhut in northeastern Madhya Pradesh state; 15 stupa carvings depict the last life of the Buddha. Indeed, stone carvings in India provide an important source for identifying which events in the lives of the Buddha were considered most important by the community. The Jataka stories are also well-known beyond India; in Southeast Asia, the story of Prince Vessantara (the Buddha’s penultimate reincarnation)—who demonstrates his dedication to the virtue of charity by giving away his sacred elephant, his children, and finally his wife—is as well-known as that of his last lifetime.
A person who has set out on the long journey to discover the path to freedom from suffering, and then to teach it to others, is called a bodhisattva. A person who has discovered that path, followed it to its end, and taught it to the world is called a buddha. Buddhas are not reborn after they die but enter a state beyond suffering called nirvana (literally “passing away”). Because buddhas appear so rarely over the course of time and because only they reveal the path to liberation (moksha) from suffering (dukkha), the appearance of a buddha in the world is considered a momentous event in the history of the universe.

B. Buddha’s Teachings
The Buddha was an oral teacher; he left no written body of thought. His beliefs were codified by later followers.
1. The Four Noble Truths
Originating as a monastic movement within the dominant Brahman tradition of the day, Buddhism quickly developed in a distinctive direction. The Buddha not only rejected significant aspects of Hindu philosophy, but also challenged the authority of the priesthood, denied the validity of the Vedic scriptures, and rejected the sacrificial cult based on them. Moreover, he opened his movement to members of all castes, denying that a person’s spiritual worth is a matter of birth. See Hinduism.

Siddhartha Gautama was the warrior son of a king and queen. According to legend, at his birth a soothsayer predicted that he might become a renouncer (withdrawing from the temporal life). To prevent this, his father provided him with many luxuries and pleasures. But, as a young man, he once went on a series of four chariot rides where he first saw the more severe forms of human suffering: old age, illness, and death (a corpse), as well as an ascetic renouncer. The contrast between his life and this human suffering made him realize that all the pleasures on earth where in fact transitory, and could only mask human suffering. Leaving his wife—and new son (“Rahula”—fetter) he took on several teachers and tried severe renunciation in the forest until the point of near-starvation. Finally, realizing that this too was only adding more suffering, he ate food and sat down beneath a tree to meditate. By morning (or some say six months later!) he had attained Nirvana (Enlightenment), which provided both the true answers to the causes of suffering and permanent release from it.
After the Buddha’s death, his celibate wandering followers gradually settled down into monasteries that were provided by the married laityas merit-producing gifts. The laity were in turn taught by the monks some of the Buddha’s teachings. They also engaged in such practices as visiting the Buddha’s birthplace; and worshipping the tree under which he became enlightened (bodhi tree), Buddha images in temples, and the relics of his body housed in various stupas or funeral mounds. A famous king, named Ashoka, and his son helped to spread Buddhism throughout South India and into Sri Lanka (Ceylon) (3rd century B.C.E.).
References:
http://www.asiahighlights.com/cambodia/religion.htm
http://www.britannica.com/biography/Buddha-founder-of-Buddhism
http://www.qcc.cuny.edu/socialsciences/ppecorino/phil_of_religion_text/chapter_2_religions/buddhism.htm
http://asiasociety.org/education/origins-buddhism
http://library.brockport.edu/c.php?g=6758&p=7009207