National Archives and Records Administration. AE 2.7:1. March 14, 1936.
Because of a case which resulted in the U.S. Attorney General having to explain to the Supreme Court why he was prosecuting two Texas oil companies over violations of regulations that didn't exist at the time of the alleged violation, Congress decided that it would be a good idea if there was a single source that recorded all regulations in force or development, as well as presidential executive orders and proclamations. Thus was born the Federal Register. (Source: http://www.archives.gov/federal-register/the-federal-register/history.pdf