[Primary Ref. Colin Rhys Lovell's English Constitutional and Legal History, Oxford University Press, c1962.]
The development of English Common Law began as royal court jurisdiction asserted on the nexus of some royal legal interest. Accordingly, cases involving crime as "offended the king's peace" and cases requiring adjudication of property permeated early assize's.
Somewhat broader than the royal inquest was the "assize." Originally the word implied the sitting of some body, usually the curia regis or the regular courts held throughout the country to administer civil and criminal justice. Later, it was used to describe the written decision of the sitting. Eventually it came to mean the entire process of royal inquest as regarded a particular situation.
Assize procedures could only be used before "royal justices" who were members of the curia regis. The realm was divided into six regular circuits, with three justices assigned to each annually, (later 21 justices into four circuits,) who would temporarily transform the local shire court into a local segment of the curia regis. Their circuit throughout the country was "iter" or "march" and so they became known as "itinerant justices."
The writs putting into motion assizes most frequently dealt with possession of land and resultant rights and obligations. These were classified according to specific actions: Petty and Grand - the former either Utrum or Possessory; the latter divided into Novel Disseisin, Mort d'Ancestor and Darrein Presentment.
Petty assizes dealt with precise matters of land possession:
"Assize utrum" was used to determine claims of the Church that land was held in frankalmoign, owing no duty but prayer. The jury would be sworn to say whether the land was indeed held in frankalmoign or some other land tenure. The itinerant justices would base their administrative decisions on the answer. If the jury said that the land was held in frankalmoign, then any question regarding it was referred to Church court.
"Possessory" assizes were more directly concerned with land possession and resultant rights.
Feudal law provided for settlement of disputes over title to land by battle or judicial combat between disputants or hired champions, with God giving victory to the right. The king felt it beneath his dignity to fight for his land rights. The Grand assize provided that no one should be dispossessed of his free holding without due process, and that no judgment would be sufficient to support such a dispossession unless it was the result of a procedure initiated by a royal summons - that is the royal court had to hear the case.
The assize of "novel disseisin" applied to a person believing himself wrongfully dispossessed of his free holding. He could secure a writ from the Chancery ordering justices to empanel a jury to answer the question whether the plaintiff at the time of his dispossession had been lawfully "seised" (in possession) of the land. If the jury's verdict was affirmative, the justices ordered the defendant to return the land and pay a fine to the king in his capacity as "the fountain of justice." Through this process, anyone with a free holding "fief" of land who refused to pay their obligation to their lord and were ejected from their land could go around his own immediate lord's court to the royal court for return of land from which he had been dispossessed.
The king was supposed to protect the interests of all vassals, regardless of whom they held. Judicial implementation of this doctrine was in the "writ of right," which any man could buy from the Chancery, and which directed the lord to do right by the plaintiff. If he failed to do so, the case could be transferred to royal court. The "writ praecipe" instructed the sheriff, (a personal employee of the king,) to see that the lord returned the land to the man buying the writ or else appear in royal court to show cause why he had not.
The assize of "mort d'ancester" was used when a lord refused to deliver inherited land to a ward when coming of age. The question asked of the jury was whether the plaintiff's direct ancestor had been in lawful possession of the land at the time of his death.
The assize of "darrein presentment" involved the right to nominate to Church posts as an element of patronage. The question asked was who had made the nomination or "presentation" or "advowson" the last time the post was vacant.