Kate Roberts (13 February 1891 – 14 April 1985) was one of the foremost Welsh-language authors of the 20th century. Styled Brenhines ein llên ('The Queen of our Literature'), she is known mainly for her short stories, but also wrote novels. Roberts was a prominent Welsh nationalist. In 1963, she was nominated for the Nobel Prize in Literature by Welsh scholar Idris Foster.

Kate Roberts was born in the village of Rhosgadfan, on the slopes of Moel Tryfan, Caernarfonshire (Gwynedd today). She was the oldest child of Owen Roberts, a quarryman in the local slate industry, and Catrin Roberts who took care of the family farm. She had two half-sisters and two half-brothers (John Evan, Mary, Jane and Owen) from earlier marriages of her parents, and three younger brothers (Richard, Evan and David). She was born in the family cottage Bryn Gwyrfai (Rhosgadfan) and later moved to Cae'r Gors. Later the life in the cottage and village made an all-important backdrop to her early literary work. Her autobiographical volume Y Lôn Wen is a memorable portrayal of the district in that period.

She attended the council school at Rhosgadfan from 1895 to 1904, and, with the help of a scholarship, the English-speaking Caernarfonshire School from 1904 to 1910. She went on to graduate in Welsh at the University College of North Wales, Bangor, which she attended from 1910 to 1913 under John Morris-Jones and Ifor Williams, and trained as a teacher. She taught in various schools in Wales (Dolbadarn Elementary School 1913–1914, Ystalyfera County School 1915–1917, and County Girls' School, Aberdare 1917–1928).

Roberts met Morris T. Williams at Plaid Cymru (the Welsh nationalist party) meetings, and married him in 1928. At that time, married women were not allowed to stay in the profession so she had to give up her job. Williams was a printer, and eventually they bought the printing and publishing house Gwasg Gee ('The Gee Press'), Denbigh, and moved to live in the town in 1935. The press published books, pamphlets and the Welsh-language weekly Y Faner (The Banner), for which Roberts wrote regularly. After her husband's death in 1946, she ran the press for another 10 years.^{[citation needed]}

In 1965 Roberts heard that Cae'r Gors had become derelict, causing her to start a campaign to save it. She bought the property and, in 1969, presented it to the nation. It was not restored until 2005, after a long campaign to raise the money. It is now in the care of Cadw as a museum presentation of Roberts.

She remained in Denbigh after her retirement and died in 1985 at the age of 94.

Alan Llwyd's 2011 biography of Roberts used diaries and letters to shed fresh light on her private life and her relationship with Morris. Llwyd suggests that Roberts may have had lesbian tendencies. For example, Roberts sent a letter to her husband describing the joy she felt when kissing another woman in Pontardawe, saying that nothing had ever made her more happy.

Her first volume of short stories, O gors y bryniau (From the Swamp of the Hills), appeared in 1925. Perhaps her most successful book of short stories is Te yn y grug (Tea in the Heather, 1959), a series about children. Of the novels that Roberts wrote, the most famous may have been Traed mewn cyffion (Feet in Chains, 1936), which reflected the hard life of a slate-quarrying family. The book was awarded a prize at the National Eisteddfod of Wales in Neath in 1934. She won the prize jointly with Grace Wynne Griffith and her novel Creigiau Milgwyn. However it was alleged that Creigiau Milgwyn was unworthy of the prize according to the historian Thomas Richards.