Miss Kate Gilnagh¹ was born in Rhyne², Cloonee, Co Longford, Ireland on 30 October 1894.³

Hailing from a Roman Catholic family, she was the second child of Hugh Gilnagh (b. 24 April 1865), a farmer, and Johanna Duffy (b. circa 1867) who had married on 7 August 1892.

She was the sister of: Mary Johanna (b. 7 September 1893), Ellen (b. 8 January 1896), Bridget (b. 16 October 1898), Thomas (b. 20 June 1897), Elizabeth (b. 27 February 1900), Margaret (b. 8 May 1902), Johanna (b. 29 March 1904), Hugh (b. 10 January 1906) and Annie (b. 7 May 1911). 

The family appear on the 1901 census living at house 18 in Rhyne, Cloonee and on the 1911 census at house 6 in the same locale. Her sister Mary "Mollie" had emigrated to the USA, leaving Ireland on board Laurentic on 9 April 1911. She lived and worked in Manhattan and soon sent for Kate to join her.

Kate joined the Titanic at Queenstown on 11 April 1912 as a third class passenger (ticket number 35851 which cost £7, 14s, 8d). Whilst aboard she roomed in cabin 161 on E-deck aft with three other Longford girls, Katie Mullin and the Murphy sisters, Margaret and Kate. She also became acquainted with fellow-Longford passengers James Farrell, Thomas McCormack and the Kiernan brothers, John and Phillip among other Irish passengers, including possibly Eugene Daly from Co Westmeath.

On the night of the sinking Kate and other steerage passengers had been enjoying a party in the communal third class areas. A rat scuttled across the floor, sending the party into excited disarray. 

Kate and her cabin mates later went to bed when a man with whom they were acquainted aboard rapped their door, telling them to get up as something was amiss with the ship. The four girls dressed and headed out to the upper decks but found their way to the lifeboats impeded by crewmen blocking their way and being determined to keep the steerage passengers in their place. When trying to pass through one barrier a crewman halted her but the intervention of James Farrell, who threatened the offending crewman with a punch if he didn't let the women through, perhaps helped save her life and she later referred to Farrell as her guardian angel. 

Kate eventually managed to get to a higher deck with the lifeboats tantalisingly close in sight, but she couldn't find her way any further. A man close by offered her a lift up on his shoulders, which she gratefully accepted, and she managed to climb over the railing to the boat deck. Spying a boat close by she made for it but a crewman again held her back, telling her it was full. Crying out that her sister was in the boat, the crewman relented and let her pass. In years later, Kate recounted that the magnitude of the disaster unfolding at the time escaped her and she naïvely thought that this was the regular, if difficult way to make it to America.

Kate eventually arrived in the USA aboard Carpathia and was described as a 17-year-old domestic and her destination address was listed as the home of a cousin Mrs Pedell at 239 East 55th Street, New York. She was eventually was reunited with her sister Mollie and to reassure her family back home that she was safe, Kate and Mollie had a portrait taken and posted to Ireland. 

Kate was eventually joined in America by another two siblings, Margaret (later Mrs Frank Murphy) and William. Her brother William died in 1917. Her sister Mollie (later Mrs Francis Vincent Boshell) died 12 October 1933. Back in Ireland her younger sister Elizabeth died as a young teenager from tuberculosis on 3 September 1913. Her father died on 6 September 1939 and her mother on 12 October 1941. 

Kate soon met her future husband, John Joseph Manning (b. circa 1893), a native of Co Roscommon who worked as a chauffeur. The two were married in 1917 and produced four children: John (b. 1919), Thomas (b. 1923), Catherine (b. 1924) and Joseph Eugene (b. 1927). The family appeared on the 1930 census as residents of 11 Cedar Street, Boston and on the 1940 census as residents of 3243 Steinway Street, Queens, New York. 

Kate was widowed when John Manning died on 19 April 1955 and in the following years became a member of the "Titanic Enthusiasts of America," later the Titanic Historical Society, and she appeared on two television programs, To Tell The Truth and the Steve Allen Show and also recalled her experiences to Walter Lord when he was writing A Night to Remember, which told parts of her story. Her picture also appeared in a 1953 Life magazine account of the tragedy.

Kate Gilnagh Manning died on 1 March 1971 in Long Island City, New York aged 76 and was buried with her husband in Woodside Cemetery, Queens, New York.

In 2018 a ballet based on the story of her rescue was premiered, choreographed by Gilnagh's great niece.