John Olsen f. 1866 in Buskerud

I'm looking for information on John Olsen, born in October 1866, presumably in Drammen (according to family lore). He was a seaman and emigrated to Florida in 1889. The 1900 US census gives the middle initial D. I don't have the 1865 Drammen/Buskerud census, and I could not find information on him in the Digitalarkivet. I would appreciate any information about his Norwegian roots.