Fredrik Waldemar Hvoslef was born in Christiania (now Oslo) and grew up in Holmestrand in Jarlsberg og Laurvig county.

He was the son of Jens Hvoslef (1783–1830) who served as Magistrate of Nordre Jarlsberg, now part of Vestfold county.

During that event two men, the local sheriff and the tradesman, were killed, while Hvoslef was attacked.

Hvoslef later served as pastor for the convicted Mons Somby and Aslak Hætta at their execution in 1854.

In 1881 he was appointed Bishop of the Diocese of Bjørgvin, and served in this position until his retirement in 1898.