Tresillian (Cornish: Tresulyan)[1] is a small village in the civil parish of St Clement, in mid Cornwall, England, United Kingdom.

agree that the name in fact translates as "farm/settlement of a man called Sulyen"[3] (a Celtic personal name from British: sulo-genos, "sun-born").

Thomas Fairfax sent a summons of surrender to Ralph Hopton who replied on 8 March that he was willing to negotiate terms.

Hopton agreed to move his army to St Allen as a gesture of trust and goodwill allowing Fairfax to occupy Truro.

The parish church of Merther was abandoned in the mid-20th century: previously it had been used occasionally, usually for funeral services.