For their purposes, the fall of Saigon is historical, but the death of Elvis is not.
From the website:
The Historical Writers' Association: an association of both historical fiction and non-fiction who have work published by recognised publishers, plus their agents and publishers. Membership shall be limited to those authors who have work published in the last 5 years, although others may be admitted at the discretion of the committee.
The Association exists to promote, sustain and raise the profile of historical writing. Membership of the association will be granted to all writers, agents and publisher staff who, in the opinion of the HWA committee, have demonstrated, either through their writing or their role in bringing such material into print, their commitment to this ideal.
For the avoidance of doubt, 'historical' shall be defined as being beyond 35 years from the point of application
