Setsutaro Hasegawa was born on 24 December 1868 in Japan. His father was from Honshu Island and his mother from Tokyo. The family moved to Otaru, on Hokkeido, during Setsutaro's childhood. Before migrating to Australia in February 1897, at age 29, Setsutaro was working as a school teacher. He arrived in Australia on the ship Yamashiro Maru during a time when migration to the Australian colonies from Asia had become increasingly difficult. The Immigration Restriction Act, which virtually banned immigration from Asia, was passed just four years after Setsutaro's arrival.
He was initially employed as a 'houseboy' by a Colonel Tucket in Melbourne and also spent some time in Ballarat before establishing a laundry business in Geelong, where there was a small Japanese community, some of whom worked for his business. In 1905 he married Australian born Ada Cole. The couple had three children, Leo in 1906, Motto Kozo in 1907 and Joe in 1911. Setsutaro unsuccessfully applied for naturalization on 6 June 1913 when he was living at 28 Peel Street North, Ballarat East. This was refused as natives of Asia were ineligible to become naturalised under the White Australia policy. In 1927 he purchased a house for 950 pounds at 21 Little Ryrie Street Geelong (100 pounds down payment with a one month interest free period to pay the balance). It was located behind his laundry business at 60 Ryrie Street, the two properties were separated by a lane.
Letters from relatives in Japan scold him for not returning home, suggesting that his original intent may not have been to stay in Australia. Setsutaro maintained contact with Japan receiving a postcard and a Red Cross certificate from the 1920s, the latter suggesting he possibly made an aid donation to his homeland.
In December 1941, Japan attacked Pearl Harbour and Japanese nationals in Australia were rounded up and interned. Setsutaro was interned at Tatura camp in northern Victoria when he was over 70 years old. He unsuccessfully appealed for release in 1942. This request was denied due to him admitting an affection for his fatherland and his obvious Japanese appearance; both of which would cause unrest in the Australian community. However, following the release of another elderly Japanese internee, George Taro Furuya, and a petition by his son Leo, who was serving in the civilian military forces, Setsutaro was released from Tatura on 3 May 1943, on the grounds of his age and poor health.
From his release until the end of the war several restrictions were placed on his movement. He could not leave his home without permission from the Deputy Director of Security for Victoria, he could not associate or communicate with persons of enemy origin other than his own family, and he could not have a telephone or radio, which could receive long range broadcasts installed in his residence. These restrictions were placed on him as it was felt his 'presence in the streets of Geelong might affect public morale'. Setsutaro was one of the very few Japanese interns who was not deported to Japan after the war, presumably because of his age, family status (Australian-born wife and children) and the longevity of his residency. Interestingly, his eldest son Leo joined the Australian Army as an engineer from 1948 until 1960, having served in the civilian military forces from 1941-1948. Setsutaro Hasegawa remained in Geelong his death which is believed to be in 1952.