Nils Georg Casper Segerstråle (31 May 1893 – 20 September 1979) was a Swedish-speaking Finnish military officer[clarification needed], chief executive and author.

He was the son of Georg Otto Segerstråle (1860–1914) and Karin Johanna Louise Tawaststjerna (1864–1933).

[1] Serving in the military, he was promoted to lieutenant and captain in 1917 and 1929 respectively.

[1] Segerstråle also served as the chief executive of Stockholmshus AB and was board member of the Stockholm Fire Insurance Office.

[1] Throughout his lifetime, he published several notable works, including Hamiltonian Castles and Manors of Sweden (1976) and Swedish Entitled Estates (1979).