In the early years of Jazz and dance bands (1920’s), the favoured instrument was the Tenor Banjo as it was louder than the acoustic guitars of the time. Remember this was pre-electric guitar and amplification.
With the advancement of the Swing era and the large band format in the 1930’s, the drive was on to create louder acoustic guitars; namely the archtop acoustic whose design ensured that the guitar had a pocket (frequency band) of its own, so it could be heard amidst the horns etc. Up to this point, the guitar was relagated to perform a backgound support role that came to be known as, ‘rhythm guitar’. Freddy Green – guitarist with the Count Basie Big Band set the template for what the guitar should do in a big band context. Typically this meant playing ‘four to the bar’ and strict time keeping in alignment with the bass a and ride cymbal. However, this approach was also characterised by a lot of chord movement rather than static support – what Freddy Green considered to be a Tenor line as a counterpoint to the rest of the band.
The above description alludes to the Swing era and Swing bands more than what followed afterwars in the post war. Other styles have encroached upon the big band format and so the guitarist has had to adjust accordingly. The aim here is to prepare the guitarist for any eventuality in regard to the resources required, the sounds needed and the actual approach taken.