About 60 mourners gathered in St Michael's Chapel in Rathbarry near Clonakilty in west Cork on Saturday for a memorial service for Lady Joyzelle Mary Carbery (87), who died in England last month.
She was buried afterwards in a family tomb on a hillside overlooking Castlefreke Castle.
The memorial service followed Requiem Mass at the Sacred Heart Church in Wimbledon last month.
Lady Carbery's remains were brought to Castlefreke on Friday, and on Saturday a hearse drawn by two black horses led the mourners from the 400-year-old castle to the small chapel.
Mourners from Britain and the United States were joined by local people.
Lady Carbery's coffin was carried by six pall bearers, including her husband and her sons. She is survived by her husband, Lord Carbery,Peter Evans-Freke, five children, 12 grandchildren and six great-grandchildren.
In his homily, Fr Pat McCarthy paid tribute to Lady Carbery. He added: "This place was rather special for Lady Carbery. I met her maybe two or three times but when she came here it was clear she had a great affection for this church and the area.
"We like to think that in some way Lady Carbery is preparing a place for all of her grandchildren to go.
"She is preparing a place of peace for all of us," he said.
After the service a lone piper, Barry Murphy, led the cortege of mourners to the family tomb.
Lady Carbery's son Stephen, who is now the owner of Castlefreke Castle and who has begun a project to restore the building, spoke briefly following the service. "It is a bitter-sweet occasion. The castle restoration is a lifetime project - I have explained to my eldest son that it is a lifetime project and that I am making a start for him," he said.