The show carries a lot of history. It was NOT the first "integrated" musical as has been claimed many times, but it was the first integrated musical to achieve smash-hit status. Also, while the OKLAHOMA! Albums of records (6 in Volume 1, 2 more in Volume 2) is often credited s the first cast album there were other cast albums done before but none were nearly as complete. Also the first volume sold over a million copies (as a set of 78-rpm discs) and another million in 1949 when it was re-released on Lp.
So, while it may not have been the very first, it was the first to score such phenomenal sales thereby starting a trend.
When you look at the careful construction of the show you see the format that Broadway would follow for the next few decades. Yes, some of the humor is forced, and the false dialect in the script can be hard to take, but the simple story and beautiful songs always win out when the show is performed with enthusiasm, dedication and conviction.
Cast albums are NOT "soundtracks."
Live theatre does not use a "soundtrack." If it did, it wouldn't be live theatre!
I host a weekly one-hour radio program featuring cast album selections as well as songs by cabaret, jazz and theatre artists. The program, FRONT ROW CENTRE is heard Sundays 9 to 10 am and also Saturdays from 8 to 9 am (eastern times) on www.proudfm.com