The Dictators Go Girl Crazy (1975)

My name is Malcolm McLaren
I have brought you many things in my time but the most successful of all
was an invention of mine they called punk rock.
 
So Malcolm Mclaren tells us in his movie The Great Rock n Roll Swindle that he invented Punk Rock.
Jon Savage, in his excellent study of Punk, England's' Dreaming, states:
In the autumn of 1975 British Punk had begun at 430 Kings Road...

The earliest reference to print to 'punk rock' came in the early 70's, and the Garage bands of the 60's were retrospectively given the label by Lenny Kaye,  writing the sleeve notes for the Nuggets album in the autumn of 1972. For the etymology of the term punk rock see Jon Savage's blog.
The Ramones made their vinyl debut in the USA in April 1976, but of course, no homegrown 'Punk' records appeared in the UK until the Damned released New Rose in October 1976 .
Listening to John Peel's Punk Rock Special (December 1976) we can hear the sort of things that punks were listening to, and much of it had been around a while (in rock n roll terms) by the time the Pistols released their debut (Anarchy in the UK) in November 1976.
Look at the first few (pre Sex Pistols) issues of Punk (which first appeared in January 1976); the mag covers Lou Reed, The Ramones, Talking Heads,  Patti Smith, Television, David Johansen, Richard Hell, The Heartbreakers, Blondie, Iggy Pop, The Dictators and Eddie and The Hotrods...
Ah, whatever. Looks like there were two things happening at the same time, New York and London. Both trying to put a bit of life back into rock, probably the first post modernist take on pop music (although Ziggy Stardust has a valid claim to this). And at some point (the release of The Ramones?) they inevitably came together.

Here's a great American LP from the pre- punk days:

Review from Punk
 

The Dictators were formed in New York City in 1973.

There's a rehash of John Holmstrom's 1977 write up on The Dictators here: http://www.thedictators.com/punkmag.html.