Karl Erik Oskar Hagblom was borne in Härnösand, in December 1854. He signed documents with C. O. Hagblom, but his whife called him Karl.

C.O. worked as a shop assistant from around 1870. He then became a businessman with his own stores in Stöde (1872- ), Fränsta and Hammar (1874- ), during the period when the railroad was being built.  The Fränsta-store became bankrupt in 1910.

In 1876 Karl married Kristina Jansson from Själevad, borne on March 31, 1852. They got 12 children - Jenny (1876-1877), Karl Filip (1877-1910), Set Konrad (1879-), Fritz Gunnar (1881-1902), Ernst Oscar (1883-1962), Gustav Rudolf (1885-1964?), Gerda Sofia (1886-1977), Arvid Teodor (1888-1889), Bror Teodor (1890-1970), Sven Verner (1892-), Ragnar Nikanor (1894-1909) & Tolv Erik Leonard (1896-).

Kristina died in Torp - a village between Stöde and Fränsta - on October 25, 1931. Karl Oskar died in Barkarby, Järfälla, outside Stockholm in 1936, visiting one of his sons.