Haakon Bryhn, Norwegian businessman and consul, was the son of the physician Nils Bryhn (born 1854), an authority on mosses. He matriculated in 1902 and spent a year at a military academy before embarking on unsuccessful medical studies. After deciding to emigrate he came to South Africa in 1908, mainly as a farmer. However, he also collected mosses at Entumeni and Eshowe in Zululand during 1908-1909, while staying with Rev. L.M. Titlestad. In 1909 he leased a property in Eshowe. His specimens, and others collected by Rev. Titlestad at Nils Bryhn's request, were described by the latter, with the help of V.F. Brotherus and others, in a paper entitled "Bryophyta nonnulla in Zululand collecta" (Several Bryophyta collected in Zululand), published in the Forhandlinger Videnskapsselkapets Kristiania (1911, No. 4, pp. 1-27). In this paper N. Bryhn and Brotherus described several new species of mosses, three of which were named after Haakon Bryhn.
Bryhn left South Africa in 1910 for Argentina, where he led an adventurous life. He returned to Norway in 1916, but left again for Ecuador in 1919, where he became a businessman. In addition he served as Norwegian consul from 1920, and as consul general from 1925. He was also the Dutch consul from 1938 to 1947, and on two occasions was appointed as a temporary Norwegian ambassador. In 1952 he was honoured as a Commander of the St Olav Order. He married Martha Jensine Ovidia Carstens in Oslo in 1908.