'Received Pronounciation,' 'Standard English' or 'BBC English', or whatever you want to call it, began to emerge in the period after American independance due to snobbery among the upper classes in England, who wanted to distinguish themselves from those from the lower classes who were becoming wealthy as a result of the industrial revolution. It took off and spread all over South East England, and from there sprung the Cockney accent and other variations spoken in London and the counties around the Thames Estuary, generally known as Estuary English.

In short, the non-rhotic regional accent of London and the South East that Americans like to refer to as the 'British Accent' evolved from a manufactured social dialect, rather than having been influenced by anything from Europe during that period. Go to any of the regions of the British Isles outside that area, particularly Scotland, Ireland and South West England, and you'll find accents that still resemble the general, rhotic American accent. 

Having said that, English as a language has always been a melting pot of words and grammar from different languages. Literally thousands of words in its vocabulary are from the Latin, Greek, Norman, Saxon and Viking languages, which have all been taken over to America by English speaking settlers. In return, a whole new vocabulary has come back across the Atlantic since the 20th century, derived from the cultures and languages of all the peoples that have settled in America.

And by the way, just because the British haven't anglicised the pronounciation of the French word 'niche' the way the Americans have, doesn't mean they don't anglicise other European words. English speaking settlers went off to America saying 'biscuit' instead of 'bisquee', (as the French word is correctly pronounced). Ironically, it's the definition of biscuit that has changed in America from its original form.

(sorry for the ramble. It's a subject I'm particularly interested in. :P )

Here I was thinking this would be an easy thing.

Yeah, 'Neesh'. I've no idea why anyone would put a 't' in that word. 'che' is a soft sound and 'ni' is 'nee'. It's a French word remember, they say 'neesh', as far as I am aware.

Yet keep in mind there is more than one way to pronounce the word 'grass' in English too based on regional dialect, as I know full well being from southern England living in the midlands.

In reality, who cares, people know what you are on about.

I thought it was always pronounced as "nice" with a silent "H". :p

English has been influenced by europe? Well, no shit sherlock, it is a european language, going all the way back to the germanic. Newsflash: The US also is heavily influenced by europe. Because, you know, the majority of people living there are european who decided to friggin' kill everyone else on the continent. =D

Really though, there is no right or wrong in language. Languages are constantly changing, it's just the way it is. In this particular case, I would go for "neesh" though, as the word is french. It may be used in english, but it is still a french word. Just like Kindergarten is a german word. If you can't make up your own words, at least pronounce the words right which you are stealing from other languages. ^^

I'm french and I'm here to help you ^^.

"Niche" is pronounced like in "Fish" with the "i" being more a "ee", and you have to pronounce the french "e" at the end of the word (almost like the "a" in "above").

Then, you'll say to your french dog :

"File dans ta niche !!!" (Feel danta nish a (danta like in santa)

French is complex ^^.

It's french so I pronounce it the correct way IE neesh.

Niech

It's how I say it.

I'm Australian, if that matters in this.

How does this go back to your statement of "US English is an oxymoron"? Seems like the typical "My English is correct, yours is wrong, cause you aren't British", which oh so many Brits seem to actually belive even though there's no such thing as a correct English.

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