* In [[English law]] and its derivatives, ''time immemorial'' means the same as ''time out of mind'',<ref>Blackstone (1765) ''Commentary'' I viii 281</ref> "a time before legal history and beyond legal memory."<ref>The [[public domain]] Webster's Revised Unabridged Dictionary (1913)</ref> In 1275, by the first [[Statutes of Westminster|Statute of Westminster]], the time of memory was limited to the reign of [[Richard I of England|Richard I]] (Richard the Lionheart), beginning 6 July 1189, the date of the King's accession.<ref>[http://www.statutelaw.gov.uk/content.aspx?activeTextDocId=1517436 Statute of Westminster, The First] (3 Edw. I cap. 5){{pn}}</ref> Since that date, proof of unbroken possession or use of any right made it unnecessary to establish the original grant under certain circumstances. In 1832, ''time immemorial'' was re-defined as "Time whereof the Memory of Man runneth not to the contrary."<ref>[http://www.statutelaw.gov.uk/content.aspx?activeTextDocId=1030774 Prescription Act, The] (2 & 3 Will. IV cap. 71) s.1</ref> The plan of dating legal memory from a fixed time was abandoned; instead, it was held that rights which had been enjoyed for twenty years (or as against [[the Crown]] thirty years) should not be impeached merely by proving that they had not been enjoyed before (holding by [[adverse possession]]).

* The [[Court of Chivalry]] is said to have defined the period before 1066 as ''time immemorial'' for the purposes of [[heraldry]].<ref>[http://college-of-arms.gov.uk/About.htm About the College of Arms] College of Arms (retrieved 24 May 2010)</ref>{{Citation needed}}