General average

For instance, should the crew jettison some cargo overboard to lighten the ship in a storm, the loss would be shared pro rata by both the carrier[2] and the cargo-owners.

In the exigencies of hazards faced at sea, crew members may have little time in which to determine precisely whose cargo they are jettisoning.

[3][5] After the fall of Rome, formal maritime law fell into disuse in Europe (maritime law scholar Jean Marie Pardessus suggests that the Digest of Justinian may have been entirely lost until a copy was discovered in Amalfi around 1135), although informal arrangements similar to the basic concept of general average was probably often followed as a practical matter.

[5] The medieval Rolls of Oléron, probably a collection of judgments from a court in Bordeaux, provided (along with much else) guidance on what is now called general average, and was taken as authoritative in many parts of Europe: the Laws of Wisbuy, as well as laws of Flanders, the Hanseatic League, Amsterdam, Genoa, and Catalonia, appear to have been copied from the Rolls of Oléron.

[5] An ordinance published by King Louis XIV of France in 1681 influenced laws in the rest of Europe, with the definition used in the French code followed in similar terms in codes and ordinances promulgated in that century and the next in Hamburg, Prussia, Denmark, Sweden, Spain, Amsterdam, Rotterdam and Middelburg.