Wow. Many thanks for all your replies.
According to all of the records that I’ve seen, and conversations with older relatives who are now dead, he was definitely German. A photograph that I was shown many years ago showed him in a sailor’s uniform and the photograph was taken in Berlin. His imprisonment in 1915 would be further evidence of this.
I have a copy of his 1877 marriage certificate and it gives his father’s name as John Witte labourer deceased.
I had assumed that he had been naturalised because it stated that he was a British naturalised but trawling through the records I haven’t found any evidence of this.
I had discovered recently that he had been imprisoned because he was German and he would have been in Southwick, I guess because his home was there. Interestingly and sadly within about two weeks of his imprisonment his wife died from heart failure.
Regarding Alice Ann Maule on her marriage certificate John Witte is listed as her father.
I had seen the report of the shipwreck but so far haven’t managed to find out much else about it although I have been told that there will be crew lists somewhere.
Where were you able to find the information from the 1921 census? It’s possible that he was in a home by then as he did die in an old people’s home.
One of the issues which complicate the research is the many different spellings of Witte, invariably it will be spelled as Witty, Whitey, White or Whittie or combinations of those. Even when it is spelled out correctly it is written down incorrectly- I know because Witte is also my surname!
Again many thanks for your input so far.