Niels Jensen (born 1942) is a Danish newspaper journalist, author, and former tactical intelligence officer in the Danish armed forces during the Cold War. He has written more than 40 non-fiction books on historical subjects and lectures on Denmark's modern history, with a particular focus on Cold War intelligence and the country's geostrategic position. His 2023 book "Hjælpen til Sønderjylland 1920-1940" (Frydenlund) examines the massive infrastructure investments that followed the 1920 reunification with Southern Jutland.
Niels Jensen gave a lecture on Denmark's vulnerable critical infrastructure and hybrid warfare at Andelen, Hadsund, on October 23, 2025.
Niels Jensen gave two lectures on the Danish Straits and hybrid warfare at Kalundborg Libraries in February 2025.
Niels Jensen appeared as a lecturer for the Foreningen Norden in Hadsund on March 6, 2025 on Denmark's security and critical infrastructure.
Niels Jensen commented on the hybrid war in the Baltic Sea and the sabotage of the gas pipelines in an interview with Folketidende.
The book "Aid to Southern Jutland 1920-1940" was published by Frydenlund on May 16, 2023 and received positive reviews in, among others, Flensborg Avis and historie-online.dk.
Journalist and former intelligence officer Niels Jensen explores the economic and social costs Denmark faced when reunifying Southern Jutland with Denmark in 1920.
A lecture on the Amager Railway's colourful history, from factory transport to its notorious role in moving latrines from Copenhagen, told through photographs and archival research.