Japanese public health insurance was first introduced for private sector employees
by the Health Insurance Law of 1922, the implementation of which was delayed until 1927 because of the
Great Kanto Earthquake of 1923. Prior to this, there were only a few private companies that offered health
insurance to their employees, and few programs providing employers’ assistance to workers for their
injuries and illnesses as specified by the Factory Law of 1911. The Health Insurance Law was enacted to
protect workers, but the coverage of the Law was partial and its benefits were not comprehensive: