RE: [St.H.Fam.Hist.] John Hallifax
There were census’s taken on St Helena. I know there are copies of the 1901, 1911 and 1931 census available in the Bodleian Library in Oxford UK.
Not sure where else you might find them.
Also this may not be of help directly to you (but you never know). However, researchers into St Helena history should know of this reference:
My father John Hallifax was born 1916 on St Helena. Could anyone point me in the right direction as how best to start my search. with regards to the geneology of his family. I have tried to find records on the net but have'nt been able to find anything relevant.
Many regards to all