When Mathias Anton Joachimsen was born on 21 September 1863, in Asp, Lundenæs, Denmark, his father, Joachim Christoffer Nielsen, was 48 and his mother, Anne Kristine Jensen, was 40. He married Christine Floe Christiansen on 5 November 1886, in Rind, Lundenæs, Denmark. They were the parents of at least 1 daughter.
Some characteristic forenames: German Hans, Kurt.
North German and Danish: patronymic from the personal name Jochim .