The Duke of Marlborough, formerly known as Jamie Blandford, has been charged with intentional strangulation.
Charles James Spencer-Churchill, a relative of Sir Winston Churchill and Diana, Princess of Wales, is accused of three offences between November 2022 and May 2024, Thames Valley Police said.
The 70-year-old has been summonsed to appear at Oxford Magistrates' Court on Thursday following his arrest on 13 May last year.
The three charges of non-fatal intentional strangulation are alleged to have taken place in Woodstock, Oxfordshire, against the same person.
He is the eldest surviving son of the 11th Duke of Marlborough and his first wife, Susan Mary Hornby. As a member of the Spencer, he is a relative of the late wartime Prime Minister Sir Winston Churchill and distantly related to the late Diana, Princess of Wales through the Spencer line of his family.
Mr Spencer-Churchill inherited his dukedom in 2014, following the death of his father, the 11th Duke of Marlborough. Prior to this, the twice-married Spencer-Churchill was the Marquess of Blandford, and also known as Jamie Blandford.
His ancestral family home is the 300-year-old Blenheim Palace – Sir Winston's birthplace – in Woodstock. However, he does not own the 18th century baroque palace – and has no role in the running of the residence and vast estate.
In 1994, the late Duke brought legal action to ensure his son and heir, who is known for his playboy past, would not be able to take control of the family seat. Blenheim is owned and managed by the Blenheim Palace Heritage Foundation.
A spokesperson for the foundation told the Press Association: "Blenheim Palace Heritage Foundation is aware legal proceedings have been brought against the Duke of Marlborough. The foundation is unable to comment on the charges, which relate to the Duke's personal conduct and private life, and which are subject to live, criminal proceedings.
"The foundation is not owned or managed by the Duke of Marlborough, but by independent entities run by boards of trustees."
Additional reporting from the Press Association.