Bernadotte was born at 7 June 1907 on Drottningholm Palace in Stockholm as the second child of Crown Prince Gustaf Adolf of Sweden and Princess Margaret of Connaught.

He worked as an assistant director at MGM in Culver City, California and served as a technical advisor on the 1937 film The Prisoner of Zenda.

His cousin Lennart Bernadotte, who two years earlier had experienced the same thing (as the first Swede in history), considered himself, and even more so Sigvard, subjected to very cruel treatment for several decades by the Royal Court of Sweden due to their marriages.

[7] On 2 July 1951, for himself, his wife and his marital descendants, Bernadotte was admitted by Grand Duchess Charlotte (head of state at the time) into the nobility of Luxembourg with the title Count of Wisborg.

[10] Over the years since then, based on precedent established in 1888 for his great-uncle Oscar,[11] and citing Oscar's title of nobility as it was confirmed by the Government of Luxembourg in 1892, Bernadotte was supported by several legal experts[12] when he petitioned for acknowledgement in Sweden of the Prince Bernadotte title as his also,[13] although he did not seek reinstatement in the line of succession to the throne as a royal prince of that country.

[14] Bernadotte went to the European Court of Human Rights in an effort to have the Government of Sweden acknowledge his princely title there, but in 2004, after his death, the ECHR declared the application inadmissible.

The wedding took place in Caxton Hall in London and the witnesses were the bride's brother Georg Patzek and a lawyer Mr Gordon.

From 1994 to 2002, he was the oldest living great-grandchild of Queen Victoria of the United Kingdom, and having reached the age of 94, he was her longest-lived male descendant until being overtaken by his younger brother Carl Johan on 29 June 2011.