Nemanja was born into a Serbian family in Bjelovar, Croatia, which was then part of the Kingdom of Serbs, Croats and Slovenes, later Jugoslavija. He was the youngest son of Andjelina and Mladen, and younger brother of Rastko. As a family they moved around a lot as Mladen was Chief of Police, they lived in Sremska Mitrovica and Ruma amongst other places.
In 1941, after the German invasion of Jugoslavija, Nemanja and his family were forced to flee to Belgrade in order to escape the Croatian Ustasa. In 1944 he joined the Serbian Volunteer Force, the military wing of 'Zbor' the nationalist movement led by Dimitrije Ljotic. Later that year the Serbian Volunteers 'Dobrovoljci', and other anti-Communist formations, were forced to leave Jugoslavija following the Soviet invasion in support of Tito's Partisans. They retreated northwards through Slovenia to Italy where they were held in internment camps, food was scarce and Nemanja became so thin he was nicknamed 'Gandhi'.
In 1948, after the war, Nemanja arrived in the UK where he was found employment in a coal mine, and hospital. During a stint at BBC Monitoring Service in Caversham, with his close friend Djoko Novakovic, he met his first wife Katherine, whom he married in 1953. Following the break up of his marriage, Nemanja worked for Rastko at his property development company in London.
In the early sixties Nemanja spent some time in Germany, where he was involved in a failed attempt to blow up the Jugoslav Embassy, was arrested and imprisoned by the German police, and eventually deported back to the UK in 1963. He met and married Pat Taylor the following year in 1964, and they lived together in Church Road, Highgate, until her death in January 2015.
In the mid 1970s Nemanja joined the Dositej Obradovic Circle, whose magazine he took over and renamed the South Slav Journal, and was its Editor until 2008. He was determined that the journal should be neutral and welcomed contributions from all political and religious groups in the Balkans. Nemanja studied at the School of Slavonic and East European Studies, University of London, where he was awarded an MA in South Slav studies.
Nemanja's political aim was the restoration of the Karadjordjevic dynasty to the throne of the Kingdom of Jugoslavija, and to that end, acted as one of the political advisors to HRH Crown Prince Alexander.
Nemanja had an interest in the martial arts and became a black belt in Judo. He loved cats and enjoyed nothing more than reading the newspaper with a glass of wine, cigarette and a cup of coffee.
He was diagnosed with Alzheimer's in 2013 which resulted in the loss of his short term memory, however he still enjoyed food, drink, music and company. His last waking moment was on November 21st, St Michael's Day, his family Slava, very fitting for a loyal and devoted Serb.