| Gudbrand Østbye | |
| Birth Date: | 2 October 1885 |
| Birth Place: | Gjøvik, Norway |
| Nationality: | Norwegian |
| Occupation: | Army officer and historian |
| Relatives: | Ragna Hørbye (mother-in-law) |
| Awards: | |
Gudbrand Østbye (2 October 1885 - 2 June 1972) was a Norwegian army officer and historian. He was born in Gjøvik, a son of factory owner Anders Østbye and Ellen Anna Hovdenak. He was married to Ragna Heyerdahl Hørbye, and thus son-in-law of Ragna Hørbye. During the Norwegian Campaign in 1940, he was in command of the 4th Brigade. Among his publications are Krigen i Valdres from 1946, and two volumes of the series Krigen i Norge 1940. He was decorated with the St. Olav's Medal With Oak Branch, and was a Knight of the Order of the Sword.[1] [2]