The Mystery of Oswego's Three Flags.

The 1756 Siege of Fort Oswego was a French victory in the French and Indian War, as the Marquis de Montcalm captured the fort and secured French control of Lake Ontario.   After his defeat of the British, Montcalm took the flags of Shirley's 50th and Pepperell's 51st.  The two flags were then hung in Quebec's cathedral Notre-Dame-des-Victoires.  When Montreal surrendered in 1760, those flags were recovered (apparently they were moved from Quebec to Montreal).

After the death of General Montcalm, his wife and mother wrote a Memorial, to answer the reproaches of Canada's Intendant, M. Bigot.  In that, they enumerate what the late marquis left them during his service in Canada: his unpaid salary, some bills of exchange, some herds and "savage clothing", along with "un drapeau dechire qu'il arracha des mains d'un Anglois a la victoire de Choueguen."  "A flag torn and snatched from the hands of an Englishman at the victory of Choueguen," is my rough translation (with the help of translate.google.com)

The captured flag of the 51st

The captured flag of the 50th

So, there were three flags at Oswego.  But what is the "torn flag?"  Could it be a Union Jack, flying above the fort?  Or perhaps the standard of the Jersey Blues?  A mystery indeed.