Communication lag during the Age of Sail: what if enemy claimed that peace agreement was signed?

Question

In the past due to the communication lag the hostilities could proceed long after peace agreements were signed. This was especially severe for the overseas territories and ships. I'm somewhat more interested in how it was handled by navies.

It's quite obvious what happened when both parties were aware of the latest news on the international relations. It's also easy to imagine what would happen if one party was aware of the declaration of war whereas the other was not. However it's not really obvious what would happen when one party was aware of the peace agreement whereas the other was not because of the risk of deception.

My question is: What were the regulations in the Western navies of the 18th and 19th century for the situation when the enemy somehow communicated the claim that peace or ceasefire agreement was signed?

Note that I'm not asking what was possible and reasonable to do in that situation, rather what the commanding officer was expected to do according to the regulations so that his actions would be considered neither a violation of his duty with risk of being court-martialed nor a breach of freshly signed peace.

Answer 1

Because European naval tradition freely allows ruses of war (such as false flag ruses) that would shock a commander of land-based forces, and even be treated as war crimes if perpetrated by land forces, a navel commander can only accept proof of a peace agreement that has been conveyed through his own chain of command.

However the commanders of both sides, both having independent command, retain some judgement in this matter. I seem to recall one instance where a widely circulated newspaper was submitted, and accepted, as proof of a peace agreement.

In 1814 Louis-Nicolas Davout did not surrender Hamburg until in receipt of a direct order to do so from Louis XVIII.

In early April Napoleon abdicated for the first time. General Bennigsen, still in command of the siege, issued two demands for surrender, but Davout refused, on the grounds that he could only accept orders from Napoleon.

On 11 May 1814 General Maurice Etienne Gérard arrived at Hamburg with orders to surrender the city from King Louis's War Minister. Even then Davout delayed the capitulation until 27 May, when 26,000 men left the city. Given the length of the siege, and the heavy losses suffered in shorter sieges further east, Davout had performed well to keep his force largely intact, but his efforts weren't appreciated by the restored Bourbons, and he was ordered to go to his home at Savigny-Sur-Orge, where he remained until Napoleon returned from exile.

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Update: Any commander who is not within ready communication with his superior is in possession of an independent command; is expected to exercise sound judgement within the scope of assigned missions and orders; and will be rewarded or punished according to his exercise of that judgement. In the British Navy that assessment could range from execution for cowardice to receipt of a peerage.

The most difficult transition was typically from peace to war, not the other way around. In peacetime there is no greater disgrace than to lose one's vessel - in wartime there is no greater disgrace than the cowardice of not risking one's vessel in pursuit of a sensible objective.

Answer 2

I remember a question about the ending of the War of 1812. The Battle of New Orleans was fought after the peace treaty was signed, and the last sea battle was fought months after the war ended.

And the answer was that when the peace treaty was signed it was known that there were warships in distant oceans. So it was estimated how long it would take for news of the peace treaty to reach different regions of the oceans. And the peace treaty said that fighting would stop by various different dates in various different parts of the world to allow time for news to reach the different oceans.

But I don't know whether naval commanders were authorized to stop fighting when they heard about peace of were ordered to keep fighting until they received orders from their own superiors to stop fighting.