From the time I became interested in yodeling I have wondered if Western Cowboy style yodeling had its beginnings in Texas. I know there is a large historically German community in and around New Braunfels, Texas. Is this a good enough connection to a European tradition?

I have reread this thread again for the manieth time. I will hold to my original comment on Jimmie Rodgers yodeling only I will state it   more precisely. Jimmie's yodeling was not show yodeling like the Sons of The Pioneers or The Riders in The Sky. His was a very solid basic yodel that got the job done and done well. With out his recording of yodels we probably wouldn't have the yodeling we do today.

Jimmie Rodgers (September 8, 1897 – May 26, 1933) was already an established musician with his band when he recorded his first recordings in August of 1927. He continued to record until his death in 1933.

In 1933 Roy Rogers, Tim Spencer, and Bob Nolan formed The Pioneer Trio in or around Los Angeles. All three were yodelers and they developed a very tight polished style of harmony yodeling. There were other yodelers and it certainly wasn't unique as a vocal style by 1933. But what the Sons were doing was special.   

I think it is fair to say that the popularity of yodeling as Jimmie Rodgers did was the impetus for The Sons of The Pioneers and Gene Autry, Elton Britt, Wilf Carter and many others to add yodeling to their repertoire.

While I grew up with The Sons of The Pioneers it was Bill Staines that reawakened my interest in yodeling and my rediscovery of Jimmie Rodgers, Frank Ifield, Slim Whitman and my discovery of Suzzy Boguss, Sourdough Slim, Don Edwards, Dave Stamey and The Riders in The Sky among others.

Don Meixner