En Garde! (1975)

Hardly an RPG at all. The Three Musketeers portrayed in a series of charts and tables.
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Superhero 2044 (1977)

The first superheroes RPG, but little more than a setting.

Boot Hill, 2nd Edition (1979)

The Old Prospector of RPGs. But smile when you say that, pardner.
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Gangster! (1979)

Run a speakeasy, bordello, or casino in your game room for fun and profit. A real rarity.
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The Revised Recon (1986)

Jungles, guerrillas, and booby traps. Let's all go to Vietnam!

The Bullwinkle and Rocky Role Playing Party Game (1988)

Hey, Rocky! Watch me pull a game out of my hat! It's not Toon, but it does have the licenses for great characters.

Space: 1889 (1988)

The British Empire expands to Mars. A very clever science fiction setting with a stiff upper lip.

Castle Falkenstein (1994)

Swashbuckling Magickal Victorian Steampunk! A clever setting and a clever, but broken game system.

Sailor Moon (1998)

Teenagers in sailor suits save the universe. An introduction to anime role playing through an adaptation of a popular licensed property.