“Stand up for what is right, even if you stand alone” (or “Stand up for what’s right, even if you stand alone”) is a saying that has been printed on many images. Authorship is uncertain.
 
“Stand up for what is right, even if you have to stand alone. I salute you with esteem and respect. Your friend. John T. Duncan” was published in the Congressional Record on March 13, 1922. “Lewis H. Cromwell, president of the Scout council, said: (...) ‘He (a Boy Scout—ed.) is taught to stand up for what is right even though he must stand alone’” was printed in the Petaluma (CA) Argus-Courier on January 26, 1943. “Speak up and stand up for what is right, even if you have to stand alone” was printed in the Index-Journal (Greenwood, SC) on October 19, 1968, from a “Citizenship in Action” program. “I saw a sign that said, ‘Stand up for what is right, even if you stand alone’” was printed on the newsgroup alt.life.sucks on August 2, 1996.
 
“‘Always stand up for what you believe in…even if it means standing alone.’— kim hanks #quote” was posted on Twitter by Arun Charles on August 26, 2009. This quote is from the book Save the Best for Last (2008) by Kim Hanks. “‘Stand up for what is right, even if you stand alone.’—Suzy Kassem” was posted on Twitter by Jennifer♡ on February 10, 2014. American writer and poet Suzy Kassem (born in 1975) does not appear to have coined or popularized the original saying, either.
 
       
Google Books
13 March 1922, Congressional Record—House, pg. 3823, col. 2:
Stand up for what is right, even if you have to stand alone. I salute you with esteem and respect.
Your friend.
JOHN T. DUNCAN.
       
26 March 1922, Austin (TX) American, “Public Commends Congressman Blanton and Condemns Congress Censure,” pg. 5, col. 8:
Stand up for what is right, even if you have to stand alone. I salute you with esteem and respect.
Your friend.
John T. Duncan.
   
5 September 1942, Pittsburgh (PA) Courier, “Standing Alone,” pg. 6, col. 2:
The ability to stand up for what considers right, even though one stands alone, is known as MORAL COURAGE.
   
26 January 1943, Petaluma (CA) Argus-Courier, pg. 3, cols. 4-5:
Lewis H. Cromwell, president of the Scout council, said: (...) “He (a Boy Scout—ed.) is taught to stand up for what is right even though he must stand alone.”
 
19 October 1968, Index-Journal (Greenwood, SC), “Club Notes,” pg. 2, col. 1:
Saluda Homemakers Hear Mr. Scurry
“Your very presence here today is evidence of your citizenship in action,” F. G. Scurry told a group of 70 Saluda Extension Homemakers and friend at the Tuesday fall council meeting.
 
Theme for the day-long program, which was held at the Corinth Lutheran Church, was “Citizenship in Action.”
 
Guest speaker, Mr. Scurry, urged the homemakers to “speak up and stand up for what is right, even if you have to stand alone.”
 
29 October 1977, The Call and Post (Cleveland, OH), pg. 10A, col. 3:
Because Ladies and Gentlemen, any man who will not stand up for what is right even if he has to stand alone, is not a man.
 
27 May 1978, The Call and Post (Cleveland, OH), pg. 21A, col. 1 ad:
May God bless Frank Battlati, I admire any man who will stand up for what’s right, even if he has to stand alone, because any man who will not stand up for what is right even if he has to stand alone, is not a man.
     
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Gandhi Marg
Gandhi Peace Foundation
1984
Pg. 41:
... fearlessness that enables one to stand up for what he believes is right even if he has to stand alone against the whole world (Long live Gandhi’s spirit for uttering this!).
     
1 May 1989, The Vidette-Messenger (Valparaiso, IN), “Home schooling trend skyrockets,” pg. 3A, col.  5:
WHEATFIELD (AP)—Janet and Dan Umlauf believe the education they can give their children at the kitchen table and the family room is superior to what can be offered at public schools.
(...)
“I (Janet Umlauf—ed.) want my children to adopt our value system, not someone else’s, so they can stand up for what’s right, even if they must stand alone.”
 
9 January 1991, St. Petersburg (FL) Times, “Fanfare sees in judge” by Jim Ross and Barbara Behrendt, pg. 1:
When you stand up for what’s right, Gary Graham has often said, you often stand alone.
   
16 June 1996, Daily Press (Newport News, VA) “The Big Finish: ‘Thank God’ for Graduation” by Alison Freehling, pg. B1:
“Inside each of you lies so much talent and potential,” said Salutatorian Rachel R. Tyson. “Stand up for what is right, even if you stand alone.”
     
Google Groups: alt.life.sucks
All Cat related alt.life.sucks traffic PLEASE use alt.animals.felines
doomie
8/2/96
(...)
I saw a sign that said, “Stand up for what is right, even if you stand alone.”
     
27 September 2000, Courier-Post (Camden, NJ), “There are more conservative blacks than media portray” by Jimmie L. Hollis,  pg. 13A, col. 4:
Of course I don’t know if I’m the only black conservative in South Jersey, but if I am alone, then I can definitely relate to the words of Justice Clarence Thomas when he said, “Don’t be afraid to stand up for what is right even if you have to stand alone.”
 
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Differentiating the High School Classroom:
Solution Strategies for 18 Common Obstacles
By Kathie F. Nunley
Thousand Oaks, CA: Corwin Press
2006
Pg. 111:
We have all seen those great inspirational posters and banners that read “Stand up for what you believe is right, even if you stand alone.”
   
Twitter
mattbacak
@mattbacak
I’m heading to bed, but don’t forget: “Stand up for what you believe in… even if it means standing alone!”
3:14 AM - 4 Feb 2009
 
Twitter
Patricia Alexander
@MsAlexander
Stand up for what is right, even if you stand alone.
9:43 AM - 14 Jun 2009
     
Twitter
Arun Charles
@livetorque
“Always stand up for what you believe in…even if it means standing alone. “
— kim hanks #quote
10:23 PM - 26 Aug 2009
 
Twitter   
Jennifer♡
@jennisanchezt
“Stand up for what is right, even if you stand alone.”—Suzy Kassem
9:08 PM - 10 Feb 2014
   
Twitter
shannen
@shannenlwrencia
Stand up for what is right, even if you stand alone - Suzy Kassem
8:17 AM - 26 Mar 2014
   
Twitter
Lauren Marshall
@lmarsh24
“Stand up for what is right, even if you stand alone.” - Suzy Kassem Courage is definitely a principle I want to live by. #acctethics
10:18 AM - 26 Apr 2014
 
Google Books
Bioethical Decision Making in Nursing, Fifth Edition
By Gladys L. Husted, Carrie J. Scotto, Kimberly Wolf and James H. Husted
New York, NY: Springer Publishing Company, LLC
2015
Pg. 158:
Stand up for what is right even if you stand alone. — Anonymous
 
Twitter
Moments & memories
@momentmemori
Stand up for what is Right even if you stand Alone. #Pakistan
12:56 PM - 28 Feb 2019