Charades -- the division of words into parts that are also words, such as PLEASURE = PLEA + SURE -- have been known for a very long time. However, charade sentences were apparently first devised by Howard Bergerson of Sweet Home, Oregon in the early 1960s.
Rogers, Hearst Sill
Word Ways: Vol. 10
, Article 5.
Available at: http://digitalcommons.butler.edu/wordways/vol10/iss2/5