Born Amy Roberta Ruck on 2 August 1878 in Murree, Punjab, British India,[1] she was one of the eight children of Eleanor D'Arcy and Colonel Arthur Ashley Ruck, a British army officer.

The family moved to Wales, where Ruck was educated at St Winifred's School, Bangor.

In 1909, Ruck married a fellow novelist, (George) Oliver Onions (1873–1961).

[2] Many of Ruck's letters and manuscripts are archived in the National Library of Wales.

[7] Berta Ruck began to contribute short stories and serials to magazines from 1905.