Lt. Col. John Cameron's profile mentions (in the Notes section, unsourced) that he served in the U.S.L. Reg during the War of 1812.
It is extremely unlikely that he served in a United States regiment. He was just a child when his immigrant Highland community chose for the King, and ended up displaced into the Glengarry area of Ontario as United Empire Loyalists. That community chose to raise militia units to fight off the American invasion in 1812.
Is the USL designation an abbreviation for one of those units? It doesn't sound like their usual kind of name. This website says that John was in the 1st Flank Company, 1st Regiment Glengarry.
That sounds much more likely.
Do any of you military history buffs have any sources on this?
Cheers
Shirlea