Background
He was as a son of banker Christian Fredrik Stoud Platou (1824–1883), brother of Christian Emil Stoud Platou and Waldemar Stoud Platou, grandnephew of Ludvig Stoud Platou, uncle of Karen Platou and granduncle of Lars T. Platou.
He was as a son of banker Christian Fredrik Stoud Platou (1824–1883), brother of Christian Emil Stoud Platou and Waldemar Stoud Platou, grandnephew of Ludvig Stoud Platou, uncle of Karen Platou and granduncle of Lars T. Platou.
He took over his father"s bank in 1885, and was the director of Hamar Sparebank until his death. From 1902 to 1097 he served as the mayor of Hamar. He was the deputy candidate ("running mate") for Axel Thallaug in the Norwegian parliamentary election, 1906 in the single-member urban constituency Lillehammer, Hamar, Gjøvik og Kongsvinger.
Thallaug and Platou, who in this particular election stood for the Coalition Party, edged out Labour"s candidates with 1,284 against 1,045 votes.
In the Norwegian parliamentary election, 1909 Platou ran against Thallaug in Hamar. As the conservative vote was split, Platou failed to carry the vote in his hometown, but lost to Labour"s Petter Nilssen with 626 against 704 votes.
Platou only stood in his hometown, and Thallaug carried the three other cities in the constituency. Before the end of the term, Platou contracted an illness and died in June 1911 in Kristiania.
He was also a board member of Volund and Hamar Dampskibsselskab, and of the supervisory commission on railways in the county. He also participated in several national elections, being a deputy member of the Parliament of Norway from 1903 to his death.