[Also moved from this thread
in reply to the preceding post]
Haddock's name was suggested by his wife, who noted that haddock was a "sad English fish" over a fish dinner.
This shows that Hergé knew Haddock was an English name for a fish...
...it transpired that there were several Haddocks who had served in the navy. Many of the Haddocks of Leigh-on-Sea served in the British Navy of the 17th century, with Admiral Sir Richard Haddock serving in the battle of Sole Bay.
...and this certainly interesting information proves that there were English/British Navy sailors and officers called Haddock.
But the use of the word English in this
part of the Wikipedia article you quote from -
Hergé then utilised the name for the English captain he'd just introduced.
- is surely just speculation, and speculation which runs counter to the fact that in Hergé's original Secret of the Unicorn
(written not that long after he'd first created Haddock) Hergé gives Haddock an ancestor who serves in the French navy. I'm not saying this in itself proves that Haddock can't
be English, but if Hergé had envisaged him as such, you'd think he'd have had his ancestor serving in the English navy (as the English translators much later did). Whatever the nationality of the sad fish that gave Hergé the name, the most obvious assumption based on the actual original books is that Hergé intended Haddock to be seen as a Belgian of some sort of Franco-Belgian descent.
In his very readable but sometimes innacurate biography, Harry Thompson makes the same assertion as the Wikipedia article does that Haddock is English in Hergé's original as well as in the English translations. He also recounts that "sad English fish" name-origin story, but also gives no firm reason to think that the character himself
was supposed to be English. Later in this biography Harry Thompson uses this unproven assertion that Haddock is English to "prove" his argument that the expedition in The Shooting Star
isn't entirely made up of German, Nazi-occupied and Nazi-sympathetic-"neutral" nationalities, so maybe that's why he's so keen on Haddock being a Brit. But, as I say, no real reason or evidence for this assumption is given.
Whether the person who wrote the Wikipedia article you quote was taking his/her "facts" regarding Haddock's nationality from Harry Thompson's book, I don't know, but it seems possible.