 Perhaps the first question on the mind of legal and philosophical historians is the issue of the degree to which, if any, contractual obligations are grounded in promissory obligations in contemporary legal regimes. This question is complicated by the different traditions and cultures involved in the long path to contemporary law, i.e., natural law theory, virtue theory, rights theory, the (anglo) common law, the continental civilian law, canon law and other theoretical approaches, which are in turn variously situated in the UK, on the European continent, and in the anglo territories (Scotland, Australia, Canada the US, etc.). The answer to the question is different in different traditions and places, and the contemporary law is the result of some complicated amalgamation of these different traditions over time. For an overview of these issues, see, e.g., Gordley (1991), Ibbetson (1999), Markovits (2011), Swain (2013), or Fried (1981, 2015).