All that can presently (February 2016) be gleaned about by internet searching is that Wm. Murray Simpson is the one-off composer of The King of Them All (1909) published by Frank K. Root and Co., Chicago, Illinois, USA.
Surfers are welcome to contribute information about this composer.
This list is arranged in chronological order and contains 3 works by Wm. Murray Simpson.
It does not claim to be complete and represents only the number of items located. Keys:ER