Mrs Lars Johan Karlsson Ahlin was born as Johanna Persdotter on 21 June 1871 in Västermo, Närlunda, Stora Sundby, Södermanland County, Sweden.

Her parents were Per, a crofter b. 25 April 1839 at Västermo, and Anna Stina (nee Larsdotter; b. 13 April 1842 at Arboga, Västmanland) Larsson. They had married 26 September 1869. Her brothers and sisters were Emma Sofia (b. 12 June 1873), Augusta (b. 26 January 1877), Charlotta (b. 5 March 1879), Per Viktor (b. 11 March 1881), Emma Christina (b. 21 June 1883), Hulda Maria (b. 6 January 1889), Carl Oscar (b. 17 April 1875), Olof Arvid (b. 29 July 1884), and Johan Emil  (a fellow victim of the sinking, b. 19 November 1886).

She had married fisherman Lars Johan Karlsson Ahlin b. 13 August 1870 at Öja, (Börsta)  on 17 June 1894 and was en route to him in Akeley, Minnesota – the couple had up to eight children.  Their known children were Anna Augusta, b. 12 September 1895 at Öja (d. 15 October 1895), Wendela Teresia, (b. 16 October 1896, d. 11 November 1896), Karl Ivar (b. 27 December 1897 d. 27 July 1899), Sven Gunnar, b. 16 August 1899 and Johan David, b. 23 May 1901. It has been suggested the couple also had three daughters who died in infancy. The third daughter seems to have been Hilda Josefina (b. 26 July 1894 at Öja), who died in her first year.

Lars Johan Ahlin went to the USA 3 August 1903 but Mrs Ahlin and her sons stayed behind for a while. Mr Ahlin came back after nearly two years to collect his family. They left Liverpool, England, 28 March 1905 as steerage passengers on the steamship Ivernia and came to Boston, Massachusetts, on or about 6 April 1905. Mr Ahlin was described as a cement labourer at the time. Their destination in the USA was 94 Sedgwick Street, Chicago, Illinois, which was the home of Victor Ahlin, Lars Johan's brother. Mr and Mrs Ahlin were able to read and write.

In 1910, they lived at 2051 Belle Plaine Avenue in Chicago and Mr Ahlin was by then described as a stock keeper in the dairy business. The Ahlin family members were not naturalized citizens of the USA.

Johanna had returned to her native Sweden to visit her parents on their farm in Närlunda and for her return to the USA boarded the Titanic at Southampton with her brother Johan Petterson as third-class passengers (Johanna travelling on ticket number 7546  which cost £9, 9s, 6d). Both were lost in the sinking. Their bodies were never found.

At the time of the sinking Johanna's postal address was given as Box 311 in Akeley, Minnesota. It is not clear if she ever lived at this address and when the Swedish consulate in New York tried to contact Johan Ahlin 10 March 1919 the letter was returned with 'Moved new address unknown.' The Mansion House Fund paid 875.52 Kr (£48) to husband and sons with a further 455.25 Kr in damages paid to her husband on 4 June 1914.

Her husband died in Chicago 29 August 1949; when he died he was listed as a widower and his wife's name was noted as Johanna. He seems to have married a Sophie Swanson 3 June 1916 and lived in Chicago before moving to Lake County, Illinois in the late 1930s. There is no mention of her in his death certificate but Sophia is listed as his wife in the censuses for 1920, 1930 and 1940.

Johanna's son Sven was never married and later worked as a timekeeper. He died on 4 January 1939 and was buried in Acacia Park Cemetery, Chicago.

Her son Johan later worked as a clerk and was married to Eleanor Christopherson (1906-1997), another Scandinavian-American, but had no children. He died in Chicago on 13 August 1983 and was buried in Montrose Cemetery in that city.