The leading Frankish tribe was the Salians and their kings united all Franks during the latter half of the fifth century. These kings were called Merovingians because they descended from Merovech whom the Franks believed to be son of a divine creature. = Frankish Kingdom 482 = Conquests to 496 = Conquests to 507. The most famous Merovingian king was Clovis who ascended the throne about 482 AD.
Grand Marnier does not go bad if it unopened and stored correctly. It should be kept from direct sunlight. It should also be protected from extreme changes in temperature. (reference-ask.com) (more).
Still, no getting around one basic truth: in principle gas can go bad. The shelf life of gasoline depends on the type of gas and the storage conditions and can range from a couple months to a couple years. One wild card is that gas you buy at the pump may already have been in storage for anywhere from days to months.