In ancient Indian history, who among the following is held responsible for initiating the spread of Buddhism to Sri Lanka?

Introduction / Context:
The spread of Buddhism beyond the borders of India is an important theme in ancient Indian history. Sri Lanka, in particular, became a strong centre of Theravada Buddhism, and traditional sources trace the origin of Buddhism in Sri Lanka to missions sent from India. Understanding which Indian ruler is credited with this early propagation helps link political history with religious and cultural diffusion. This question focuses on identifying the ruler associated with sending Buddhist missions to Sri Lanka.

Given Data / Assumptions:

• The region in focus is Sri Lanka (then known as Lanka or Tambapanni).
• The religion in focus is Buddhism.
• Options include Ashoka, Mahavira, Parsavanth, and Chandra Gupta Maurya.
• Information from Buddhist chronicles such as Mahavamsa is assumed as historical background.

Concept / Approach:
Emperor Ashoka of the Maurya dynasty is renowned for his patronage and active promotion of Buddhism after the Kalinga war. Buddhist chronicles state that he dispatched missions to various regions, including Sri Lanka. His son Mahinda (Mahendra) and daughter Sanghamitta are traditionally credited with introducing Buddhism to Sri Lanka, but these missions were sent under Ashoka's authority. Mahavira and Parsavanth are Jain Tirthankaras, associated with Jainism rather than Buddhism. Chandra Gupta Maurya was an earlier Maurya ruler connected more with the spread of Jainism later in his life. Therefore, Ashoka is the correct answer in this context.

Step-by-Step Solution:

Verification / Alternative check:
Most standard history textbooks clearly state that Ashoka sent Buddhist missions to various regions, including Sri Lanka, where Buddhism took strong root. The story of the Bodhi tree sapling being taken to Sri Lanka by Sanghamitta, Ashoka's daughter, further reinforces this connection. No such missionary role is attributed to Mahavira or Parsavanth, who are central figures in Jainism, or to Chandra Gupta Maurya in the context of Sri Lanka. This consistent narrative confirms Ashoka as the correct choice.

Why Other Options Are Wrong:

• Mahavira: The 24th Tirthankara of Jainism, associated with Jain doctrines, not with sending Buddhist missions abroad.
• Parsavanth: An earlier Jain Tirthankara, also unrelated to the spread of Buddhism.
• Chandra Gupta Maurya: Founder of the Maurya dynasty, later associated with Jainism, but not documented as the initiator of Buddhist missions to Sri Lanka.

Common Pitfalls:
Students sometimes confuse Jain and Buddhist personalities because they appear close together in the ancient timeline. Another pitfall is to assume that any Mauryan emperor mentioned must be responsible for all religious activities in that era. To avoid confusion, it is crucial to associate Ashoka specifically with the promotion of Buddhism and with missions to Sri Lanka and other regions, while remembering that Mahavira and Parsavanth are Jain figures.

Final Answer:
The ruler held responsible for initiating the spread of Buddhism to Sri Lanka is Ashoka.