He was born in Tromsøe as the son of Michael Wide Holmboe and his wife Anna Rasch Schjelderup. He had several brothers and sisters, including businessman Hans Conrad Holmboe. His grandfather of the same name was a bailiff, and his uncles Even Hammer Holmboe and Hans Holmboe and Leonhard Christian Borchgrevink Holmboe became involved in politics. In 1851 he married Bergithe Caroline Killengren from Tromsøe. The couple had a son Michael Holmboe and one daughter. Bergithe died in 1853, a week after giving birth to the daughter. In 1856 Jens Holmboe married Caroline Juell, who hailed from Kragerø. The couple had one daughter. Caroline Juell died after giving birth to her. Michael Holmboe later had a son named Jens in 1880, who became a noted botanist.
Career
Jens Holmboe graduated as cand.jur. in 1845, and was appointed as bailiff and district stipendiary magistrate in the northern city ofHammerfest in 1856. He was elected to the Norwegian Parliament in 1859, 1862 and 1868, representing the constituency of Finmarkens Amt. which at that time included both Finnmark and Troms. When Finmarkens Amt was split in two in 1866, Holmboe became County Governor of Finnmark. He held this position until 1874. He then began a career in the executive branch of government. He was appointed Minister of Justice and the Police on 30 April 1874. He left on 30 September the same year, only to become member of the Council of State Division in Stockholm the next day. He held this position for exactly one year, except for a period between 26 May and 20 July 1875. Then, on 1 October 1875, he was appointed Minister of Finance and Customs. On 1 November 1876 he was appointed Minister of Church and Education, and on 1 October the next year he became Minister of the Navy and Postal Affairs. Exactly one year after that he was moved to the Council of State Division in Stockholm. On 1 September 1879 he was appointed Minister of Finance and Customs for the second time, a position he held until 31 August the next year. On 1 November 1880 he became Minister of Church and Education again, leaving exactly one year later, and with a short hiatus in September 1881. Ten months as Minister of the Navy and Postal Affairs followed, before one year as Minister of Justice and the Police. From 1 September 1883 he was a member of the Council of State Division in Stockholm for the third time. Ultimately, he was impeached in March 1884, together with the rest of the cabinet Selmer. Some sources state that he, during this period, headed each government ministry in Norway, but this is not true. He was never Minister of Defence, nor Minister of Auditing. Having been impeached from his government seat, he again stood for election to Parliament, and was elected for the term 1886–1888. He was appointed stipendiary magistrate in Arendal, and then district stipendiary magistrate in Moss. He was elected for one final term in Parliament in 1889, representing the constituency Smaalenenes Amt. He died in 1891 in Kristiania.