mercenlage (m<<schwa>>r-s<<schwa>>n-law). [fr. Saxon myrcnalag] The law of the Mercians. • This was one of the three principal legal systems prevailing in England at the beginning of the 11th century. It was observed in many midland counties and those bordering on Wales. — Also spelled merchenlage (m<< schwa>>r-sh<<schwa>>n-law). — Also termed lex merciorum (leks m<<schwa>>r-shee-or-<<schwa>>m); Mercian law (m<<schwa>>r-shee-<<schwa>>n orm<<schwa>>r-sh<<schwa>>n). See DANELAW; WEST-SAXON LAW.
“[A]bout the beginning of the eleventh century there were three principal systems of laws prevailing in different districts …. The Mercen–Lage, or Mercian laws, which were observed in many of the midland counties, and those bordering on the principality of Wales; the retreat of the ancient Britons; and therefore very probably intermixed with the British or Druidical customs.” 1 William Blackstone, Commentaries on the Laws of England 65 (1765).
[Blacks Law 8th]