Monterey Jack is one of the few distinctively American cheeses, not imported from somewhere else but actually developed on the North American continent. It's not to be confused with 'American Cheese', a strange and disquieting pale-orange and tasteless cheese imitation.
The cheese originated in the 18th Century as a queso del pais, or country cheese, made by the Spanish missionaries in California. The name apparently originated in the 1880s when a businessman named David Jacks began shipping the cheese out in large quantities from the pleasant coastal town of Monterey. Somewhere along the line the 's' vanished from his name1.
The Low - Fat Low - Down
Monterey Jack, known colloquially as 'Jack', has a fat content of roughly 25% and a water content of roughly 45%.
Monterey Jack is a fairly soft cheese, similar to mozzarella, but with a less robust flavour, as it is normally made from skimmed milk. It's creamy in texture and flavour, but is distinctive and pleasant. This retiring taste leads to flavoured Jack cheeses, with 'Pepper Jack' filled with bits of chopped jalapeno peppers being quite common in the western United States. If you look hard enough, you'll also find other flavours including pesto, garlic, onion, smoked salmon, habanero2 and caraway.
These days, about a tenth of the cheese produced in California is Monterey Jack. In 1996 this amounted to over 100 million pounds of cheese (very nearly 50 million kilos for those of you with more rational systems of weights and measures).