king's peace

noun

(in early medieval England) the protection secured by the king for particular people or places
(in medieval England) the general peace secured to the entire realm by the law administered in the king's name

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012