PosonIn Sri Lanka the establishment of Buddhism on the island is celebrated about a month after Vesak with the Poson festival. The major activities take place at Anurādhapura and Mahintale, where thousands of people come to honor Mahinda, the patron saint of Sri Lanka, who is reputed to have brought the dharma to the island at the request of his father, King Aśoka. Later, Mahinda's sister, Sanghamittā, came to the island to establish a Buddhist order of nuns. She brought a branch of the sacred bodhi tree with her, which was planted in the capital. Paying homage to the sacred bodhi tree is an important part of the festivities that take place.
Swearer, Donald K. "Buddhist Religious Year." Encyclopedia of Religion, edited by Lindsay Jones, 2nd ed., vol. 2, Macmillan Reference USA, 2005, pp. 1303-1309. Gale eBooks, https://ezproxy.ecc.edu:3555/apps/doc/CX3424500455/GVRL?u=erieccn_main&sid=GVRL&xid=2845e464. Accessed 4 Sept. 2020.