In 1976, Nelson recorded his debut long play album "Diggy Liggy", which turned out to be his major breakthrough in Norway, and which became the number one country music record in Norway that year. A few years later he finally achieved fame in USA, becoming the first Norwegian singer to perform at the Grand Ole Opry in Nashville. Here he was also named «International Star of the Year» in both 1981 and 1982. In 1989 he was awarded the Country Music Roundup in London, the highest recognition of country music in Europe. Since then, he has been credited by many Nashville producers as being one of the artists to make way for «The modern Nashville sound».
In the spring of 1991, Nelson was diagnosed with lung cancer after a lifetime of smoking. The illness took its toll on the singer, who nonetheless refused to give in, staying active until the very end. During his final year he began a collaboration with famed country artist Skeeter Davis, but the duo was sadly shortlived, it's only product being the 1991 album "You Were Made for Me".
On June 8, 1992, Nelson was on tour in Denmark, when he died suddenly whilst relaxing in the backroom, waiting to take the stage in Ålborg. He was 52 years old.
Since his death, Nelson has been given tributes by both his son, Rudi Nielsen, who performs with his own band playing his fathers songs. He also performed and recorded with his father from 1979-1992. Norwegian group Vassendgutane has also done covers of Nelsons songs both on records and live, whith two of the members in the band being former band members in Nelsons own touring band.