“Texan Spoken Here” appeared as a sign in a Mexico City shop in 1955. It was later made into a bumper sticker.
 
   
Zazzle.com
Texan Spoken Here Poster
   
22 January 1955, Oneonta (NY) Star, pg. 1, col. 1:
New Sales Approach
MEXICO CITY, Jan. 21 (UP)—The owner of a silver shop catering to U. S. tourists came up with a new sales approach today. A sign in his window says: “Texan spoken here.”
   
4 March 1955, Lima (OH) News, pg. 24, col. 2:
A curio shop in the French Quarter of New Orleans has a sign saying: “Texan Spoken Here.”     
   
1 April 1956, Lima (OH) News, pg. 14C, col. 4:
English, Too, Maybe?
MEXICO CITY (UP)—Sign in a downtown store window: “Texan spoken here.”
 
23 September 1965, Dallas Morning News, section A, pg. 1:
Sign, says Marlene Steves, in The Steak Pit in the New Orleans French quarter: “TEXAN SPOKEN HERE.”
     
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From: Steve Rhodes

Date: 1997/01/05
Subject: REVIEW: THE WHOLE WIDE WORLD (**)
 
I found the “Texan Spoken Here” sign at the soda fountain quite ironic since few of the characters even attempt an accent.