Trials of the Middle Ages: A Chronology (510 to 1440)

c. 510
First references in the literature to trial by ordeal.  Specifically, there are references to men "being adjudged by the cauldron."  The practice seems to have been of Frankish origin.  Trial by cauldron is used in the decades that follow in cases involves theft, perjury, contempt of court, adultery, and various other cases.
Lombard law makes reference to slaves undergoing trial by cauldron.
A dispute over ownership of a monastery is settled using the ordeal of the cross.  In this ordeal, the winner of the dispute is person who can keep his arms outstretched in the form of a cross for the longest period of time.
c. 800
The use of trial by ordeal spreads during the reign of Charlemagne.  The variety of ordeals multiplies. For the next four hundred years, trials by ordeal will be frequently used throughout much of Europe.
Earliest reference to the trial by ordeal that requires the accused to walk barefoot over hot ploughshares. 
818 or 819
Lewis the Pious bans the use of the ordeal of the cross.
The trial of Queen Teutberga.  Accused of various sexual offenses by her husband, King Lothar, Tetuberga calls one of her retainers to undergo the trial by cauldron on her behalf.
January 897
The Cadaver Synod (or "Dead Pope" trial) at Basilica San Giovanni Laterno.  The deceased Pope Formosus is found guilty of a series of crimes.  The corpse is stripped of its vestments and the three fingers the Pope had used for blessings are cut off.  Later in 897 the prosecuting pope, Pope Stephen VI, is murdered.
Queen Uta of Germany is acquitted of adultery after 82 knight compurgators affirm her chastity.
Beginning of the Icelandic Commonwealth period.
c. 1012
In Iceland, after men loyal to a chieftain named Flosi burn Njal's farmhouse, killing many members of Njal's family, Njal's nephew Kari Solmundarson and other kinsmen take the murderers to court. The trial that follows is full of twists and turns and ends in a bloody massacre.  The story of the trial--most likely a mix of truth and fiction--is told in the most famous of the Icelandic sagas, The Saga of Burnt Njal.
If later stories are to be believed (which they probably shouldn't be), Queen Emma of Normandy (the mother of Edward the Confessor) is found innocent of adultery with the Bishop of Winchester after walking over hot ploughshares without injury.
Trials by ordeal become commonly used in trials for heresy.
Pope Innocent III approves of the practice of allowing judges, on their own motion, to make inquiries in criminal cases.  The practice, when used in cases involving heretics especially, will become known at The Inquisition.
Pope Innocent III issues a decree prohibiting priests from participating in trials by ordeal. 
Pope Gregory IX persuades Emperor Frederick II of Germany to burn heretics after they are identified and convicted by Church courts.
January 18, 1386
Jacques Le Gris allegedly rapes the wife of Jean de Carrouges.  Margeurite tells her husband about the attack when he returns home several days later. 
July 9, 1386
Le Gris and Carrouges present themselves at the Palais de Justice in Paris.  Carrouges accuses Le Gris of raping his wife; Le Gris announces his intent to sue for defamation.  They each throw down a gauntlet.
September 15, 1386
The French Parlement announces that is unable to reach a verdict in the Carrouges-Le Gris case.  The two men will fight a duel to death.
December 29, 1386
Carrouges and Le Gris engage in trial by combat ("the last duel") at a jousting arena at an abbey north of Paris.  Carrouges drives a dagger through Le Gris's neck, killing him.  King Charles VI presents Carrouges with a prize of 1,000 francs.
Czech priest and philosopher Han Hus is tried and executed in Prague for heresy.
May 30, 1431
Joan of Arc is burned at the stake after being declared a relapsed heretic.  Specifically, Joan of Arc was determined to have donned the clothing of a man, which she said she did in order to protect her virginity.  Joan, in her ordinary trial, faced a twelve-count indictment.  She previously had escaped execution by signing an abjuration document.
Serial murderer and sadist extraordinaire (Gilles was charged with torturing and killing 140 children) Gilles de Rais is convicted and executed in France.