"Charles XV also Carl (Carl Ludvig Eugen); Swedish: Karl XV and Norwegian: Karl IV (3 May 1826 – 18 September 1872) was King of Sweden (Charles XV) and Norway (proclaimed as Charles XV, but in recent times referred to accurately as Charles IV) from 1859 until his death. Though known as King Charles XV in Sweden (and also on contemporary Norwegian coins), he was actually the ninth Swedish king by that name, as his predecessor Charles IX (reigned 1604–1611) had adopted a numeral according to a fictitious history of Sweden." - (en.wikipedia.org 08.11.2019)
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