The book Spin Again describes how the 1960s was the heyday for TV advertising of boardgames. I remember seeing quite a few, in particular I remember Stratego being advertised. The commercial touted the fun of "Stra Teeee Go!"
This is a different commercial that I don't remember seeing, but seems to be from about the same time:
And it was, and still is, fun.
Like many older games the pace is a little slow by current standards. Most pieces move a single space at a time and player alternate moving a single piece at a time. This isn't much of a problem in games with a few pieces such as chess or checkers, but Stratego starts with 40 on a side, so there's a few slow spots.
On the other hand, having the pieces stand upright so you can hide the value and identity of each unit adds to the excitement and adds some bluff as well as strategy to the game. It's the forerunner to concepts more fully developed in the block wargames that are popular now.
The game was my introduction to military ranks as a child, and I was fascinated by the sergeants, lieutenants, captains, etc. I made it to real-life major, myself, but I had a chance to be a colonel, general or marshal often enough on the game board.
The game is still a good introduction to strategy games. The concept is simple enough that a grade schooler can grasp it, but has a enough subtlety in play that it will wear well over time.
I lost my original game long ago, as kids will, but Target has a nice edition in a wooden box that includes plastic pieces that are exactly the same as the ones I used as a kid. Unlike the European and newer U.S. editions, which rank the marshal at 10 and go down, this edition preserves the classic ranks of 1 for a marshal, 2 for the general, etc.
In practice there's no difference in play and I haven't found that anyone has trouble remembering that No. 1 beats No. 2, so I like the old way better, but that's probably just creeping old-fartism at work. I'll admit that having high beat low is more in keeping with gaming conventions.
Whether high or low, it's still a lot of fun either way.