Remembering their recent success with the Six Million Dollar Man line of action figures, Kenner decided to create a new line of Star Wars figures in that size - roughly 12" in height. It meant an increase in manufacturing and other costs, but if successful it would also mean an increase in profit.
Although often referred to as 'the 12-inch Star Wars figures', the line was correctly referred to as Kenner's 'Large Size Action Figures.' Most of the figures did indeed measure one foot in height, while some were larger (Chewbacca, for example, at about 15") and some smaller (Jawas, at 8").
The figures themselves were well-constructed, with detailed clothing and facial features, so that they tended to make Kenner's smaller figure line look crude by comparison. They were also sold in attractive window boxes that prominently featured two photographs of the character, the Star Wars logo, and the figure itself.
Eleven of the figures were released soon after the beginning of the line. These included Darth Vader, Luke Skywalker, Han Solo, Princess Leia, Chewbacca, R2D2, C3PO, Obi-Wan Kenobi, Boba Fett, a Jawa, and a Stormtrooper. Early in 1980 a twelfth figure, the bounty hunter IG-88, was released; but by that time the Large Size line was pretty much finished with consumers.
The line hadn't been as successful as the 3" figure line, which would keep on chugging along for several years. One reason was that at the retail price point, kids could only get the one Large Size figure in most cases, without being able to buy an adversary or companion for that character - after all, action figures play best in groups. Another reason was that the 3" line just had so many characters that for not much money, a kid could soon amass a huge army of them to recreate elaborate scenes from the movies; this would have been impossible for larger (and pricier) figures.
Kenner's Large Size Star Wars action figures are in high demand from vintage Star Wars collectors; naturally, those that remain in their original packaging, or are otherwise clean and with all parts unbroken and accounted for, command a premium. However, as time passes these larger (and often more fragile) figures become more and more difficult to find.