According to the Sri Lankan chronicles, the Buddhist emperor who sent missionaries to Sri Lanka was Ashoka.
Ashoka ruled much of the Indian subcontinent during the third century BCE. Buddhist tradition holds that after the violent Kalinga War, he embraced Buddhist principles and supported the spread of the Dharma. His inscriptions, carved on rocks and pillars, provide important evidence about his policies and religious patronage.
The Sri Lankan chronicles Dipavamsa and Mahavamsa state that Ashoka sent his son Mahinda to Sri Lanka. Mahinda is said to have introduced Buddhism to King Devanampiya Tissa, while Ashoka’s daughter Sanghamitta is traditionally associated with bringing a branch of the Bodhi Tree and establishing a community of nuns.
These accounts combine historical memory with religious tradition, so historians distinguish between the inscriptions and later narrative sources. Ashoka’s role in supporting Buddhism, however, is widely recognized.