Yes we do have dialects here in UK - a dialect is quite distinct from an accent. Probably the best known English dialect is Cockney Rhyming Slang - but speaking it is a whole new world in it's own right.
Before you visit any of the Cockney Dialect links below - you should be warned that they contain rude swear words as well as ordinary words. To be fair, the English language is full of what we call 'four letter words' - swear words.
http://www.thedialectdictionary.com/view/letter/Cockney+Rhyming+Slang/
http://en.wikipedia.org/wiki/Cockney
There are plenty of other examples here in UK of local dialects - probably the best well known is the Yorkshire Dialect - this link will explain about that.
http://www.yorkshiredialect.com/
If we go back to the early 19thC here in UK, the English language was spoken differently in each region of the UK. It is only when we started to put our children into schools properly for the first time that things began to become standardized in terms of received and spoken English.
Back in the 18thC an Italian gentleman published a book of English Phrases for travellers. He called his book, "English as She is Spoke" - this book became very popular here in UK - the title alone speaks for itself - a mad and wonderful misuse of English - very amusing.
More
https://www.youtube.com/watch?v=Uvh6ra1gbjc
https://www.youtube.com/watch?v=0VIzQEBVmNI
https://www.youtube.com/watch?v=dBBQAljhFEM
The English language starts life out there on the streets - it is entirely democratic. There is no committee dictating to the people how to speak or what to say. New words arrive almost by the day. The OED (Oxford English Dictionary) is responsible for ensuring that popular new words eventually become 'standard English'. One such recent word is 'chav' a low life person. This word 'chav' comes from the Roma language and was just slang, but now it's official.
If you look in an English dictionary you'll also find an army of Italian words too. Not forgetting every Greek word we could collect too.
Scroll down at bit at this next link and you'll find some if not all, of the Italian words we've stolen and put into English - why bother making them up when you can just take them from someone else's language?
http://www.translationdirectory.com/glossaries/glossary171.htm
This next will give you a sample of a kind of English which you will no longer hear anywhere. It is not Shakespearean English - instead it is a quality of English spoken by the upper class English way back in the 19th and early 20th centuries.
https://www.youtube.com/watch?v=px5hvNWoVLE
Finally, a Cockney from the 1950s
https://www.youtube.com/watch?v=Da8LcOMQU08
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