Final answer:
In Theravada Buddhism, the role of an arhat is as someone who has achieved enlightenment and liberation from the cycle of rebirth through meditation and adherence to the Buddha's teachings. The historical Buddha, Siddhartha Gautama, taught in northern India around 535 BCE, spreading the core principles of the Four Noble Truths and the Eightfold Path to a life of enlightenment.
Step-by-step explanation:
Theravada Buddhism is considered the most ancient branch of Buddhism and is predominant in Southeast Asia and Sri Lanka. The follower who achieves enlightenment in Theravada Buddhism is referred to as an arhat. Unlike in Mahayana Buddhism where the equivalent to an arhat in spiritual development is a bodhisattva, the role of the arhat in Theravada is accentuated as an individual who has reached Nirvana and thus liberated themselves from the cycles of rebirth. In Theravada, much emphasis is placed on meditation and adhering to the Buddha's original teachings to achieve this state of enlightenment.
The historical background of Buddhism dates back to around 535 BCE with the teachings of Siddhartha Gautama, the first Buddha, in northern India. Buddhism has since spread beyond its origins, shaping through various cultures and branching out into different schools such as Theravada and Mahayana. The core of Buddhist philosophy lies in understanding and implementing the Four Noble Truths and following the Eightfold Path, leading to a life free from suffering and ultimately to the attainment of Nirvana.