Both military and civilian courts have rules that govern the acceptance of a guilty plea. Based generally on the civilian rule, Rule for Courts-Martial (R.C.M.) 910 substantially restricts the military judge in the methods whereby he can accept a guilty plea in contrast to the broader discretion given his federal counterpart under Federal Rule of Criminal Procedure 11 (“Rule 11”). Under traditional statutory and regulatory interpretation, Rule 11 may inform the interpretation of R.C.M. 910, but it does not control. Unless R.C.M. 910 conflicts with the Uniform Code of Military Justice (UCMJ) or the Constitution, it is granted the force and effect of law. But as I was reviewing decisions of the Court’s 1968-1969 term my ongoing research project, I had the opportunity to re-read United States v. Care, the seminal case establishing the standard for determining the factual basis for a guilty plea in military courts-martial. In doing so, I was reminded of the contribution legal history can make to the understanding and development of military law.