The Action of 31 May 1809 was a naval skirmish in the Bay of Bengal during the Napoleonic Wars. During the action, an Honourable East India Company convoy carrying goods worth over £500,000 was attacked and partially captured by the French frigate Caroline. The three East Indiamen that made up the convoy fought against their opponent with their own batteries of cannon but ultimately were less powerful, less manoeuvrable and less trained than their opponent and were defeated one by one; only the smallest of the three escaped. The action was the first in a string of attacks on important convoys in the Indian Ocean by French cruisers operating from Île de France and Île Bonaparte during a concerted campaign against British shipping in the region.