[1] In 1846, Peter Petersen received his burghership in Christiania, and took over his father's dry goods store, including the building at Karl Johans gate 16.

[4] He also founded Christiania Mekaniske Væveri in 1847 together with Iver Olsen and the Nydalens Compagnie associates Adam Hiorth, Hans Gulbranson and Oluf Nicolai Roll,[5] and was among the owners of Grorud Kledefabrikk.

Petersen owned the country house "Gimle" near Frogner Church, and led an active upper-class social life there.

He headed the arrangement committee for the famous speed skating race at Frognerkilen in 1885 between Axel Paulsen and Renke van der Zee.

[1][4] The family company was later run by Hans Bergsland from 1916 to 1922, and thereafter by Oscar Midtskau under the name Peter Petersen & Co.s Eftf.