Knud Valdemar Gylding Holmboe (April 22, 1902 Horsens Denmark - October 13, 1931 Aqaba, Jordan) was a Danish journalist, author and explorer who converted from Protestantism to Catholicism in 1921, and, after a sojourn in North Africa, ultimately converted to Islam in 1929. Six years later, he published a book of his experiences on a journey through Libya, that later became famous. The book exposed the maltreatment of the population the author had witnessed on his journey and the atrocities committed by the Italian colonial power. Holmboe was murdered on his way to Makkah in Aqaba in October 1931.
Knud Holmboe is the elder brother of Danish composer Vagn Holmboe.
Knud Holmboe was born as the eldest son of a well-known Danish merchant family in Horsens, Jutland. In his late teenage years he became more and more interested in religion and philosophy, and at the age of twenty, he moved into a monastery in Clervaux/Clerf, in northern Luxembourg, converting to Catholicism in 1921.
After finishing an education as a journalist, he started to work for various Danish local papers. However, in search of deeper religious knowledge, he traveled to Morocco in 1924, and became acquainted with Islam. During a meeting with a sheikh, he realized that he belonged to Islam and converted the following year. His first book "Between the Devil and the Deep Sea. A Dash by Plane to Seething Morocco" was translated from the Danish and published in 1924 by Klinte Publishers.
After returning to Denmark, he wrote two books recounting his experiences in Morocco. In 1925, he began a journey across the countries of the Middle East (Turkey, Syria, Palestine, Iraq and Persia). In 1927, he travelled through the Balkan and witnessed in Albania the mistreatment of the population by Italian troops. He took a photograph of the hanging of a dissident Catholic priest by Mussolini's soldiers in Albania. This picture was published in newspapers around the globe and, along with articles that went public all over Europe, infuriated the Italian authorities.