That quote about 'they came for the..'

Could somebody please tell me about the quote where it goes on about them coming for X, but I wasn’t an X, then they came for Y, but I wasn’t a Y, etc… ?

I would like to know what the actual quote is, and who wrote/said it. Thanks.

First they came for the Jews
and I did not speak out
because I was not a Jew.
Then they came for the Communists
and I did not speak out
because I was not a Communist.
Then they came for the trade unionists
and I did not speak out
because I was not a trade unionist.
Then they came for me
and there was no one left
to speak out for me.

Pastor Martin Niemöller

Quoteland.com gives the quote slightly differently:

“In Germany, they first came for the communists, and I didn’t speak up because I wasn’t a communist. Then they came for the Jews, and I didn’t speak up because I wasn’t a Jew. Then they came for the trade unionists, and I didn’t speak up because I wasn’t a trade unionist. Then they came for the Catholics and I didn’t speak up because I wasn’t a Catholic. Then they came for me – and by that time there was nobody left to speak up.”
-Martin Niemöller

However, I seem to recall that there was some controversy about whether Niemöller actually first said this or whether he simply took the credit.

I’ll see if I can’t track it down

Here’s what I’ve found:

I obtained this from this page, the FAQ of the United States Holocaust Memorial Museum. Personally, I found the following quote much more chilling than the above. At the museum, it’s on the wall in a room containing a very upsetting number of shoes, piled quite deep:

Thanks to all who responded.

[OT]
Max Torque, I remember seeing the piles of shoes at Birkenau/Auschwitz. They definitely make you stop and think, don’t they. The mind boggles and sometimes is numbed by the numbers, but things like shoes or other personal belongings can really bring the tragedy back to the basics.
Never again, I hope.
[/OT]

There’s an interesting discussion about the quote on this site: http://www.liv-coll.ac.uk/pa09/europetrip/brussels/neimoller.htm#quote

Part of this confusion was created by Niemoller himself who apparently often used slightly different versions of the quote at different public speaking events.

The earliest reference I can find to the quote is from this site http://www.wathena406.k12.ks.us/clarkson/Lesson%20Plans/niemoller.htm that says

Here’s a source that could be verified by someone ambitious enough. From this site