The first Somerville to land in Ireland in 1690 was a refugee, fleeing persecution of the Church of Scotland of which William Somerville was a minister. He took his family and rowed twenty miles over rough water to Ulster, where they found refuge through family connections. He died four years later aged just 51.

Thomas Somerville was aged two when he made the journey by boat. The younger of two sons, he decided to make his career in the Church of Ireland. He went to Trinity College, Dublin, and became ordained. The family fortunes changed when he married Ann Neville in 1723. She came from a family of means,  had an annuity of £500 a year, and they prospered and had eight children. In 1732 the family moved to West Cork, Thomas having landed the living as the Rector Of Castlehaven. He bought as his vicarage the old O’Driscoll Castle next to the church at Castlehaven Strand and although both now lie in ruins, there still remains in the house his portrait, his stick and his 1685 edition of Bedel’s Irish Bible. He died in 1752.

Of the four sons of Thomas and Ann, three brothers emigrated to Savannah, Georgia and became very prosperous. The eldest son, also called Thomas, lost an eye in an accident at Trinity. This prevented him from being ordained, so instead he built up a fleet of ships with which he traded very successfully with America. He married Mary Townshend (the first of three consecutive marriages to the Townshend family) and they had eleven children. He bought the estate and built Drishane and several other notable buildings in Castletownshend, notably the warehousing on the main harbour quay, the Custom House and his Dower  house on the Mall.