Having composed a Viola Concerto in 1929, and Violin Concerto in 1939, it was in 1957 that Walton composed his third concerto – for Cello.
Like his other concerti, it opens with a moderately paced movement, moving to faster movement. This concerto then has theme and variations as its third and final movement.
There is a good analysis of the work at Wikipedia:
https://en.wikipedia.org/wiki/Cello_Concerto_(Walton)#Analysis