Wired Magazine has created a superb visual guide on the history of the manga phenomenon in the US. The guide itself has been created in the style of a manga comic and chronicles the growth in popularity of "Japan’s coolest export" to the US. Read how Japanese TV shows, movies and pop culture icons popularized the genre in America.
Snip from the site:
We decided that the best way to explain the increasing popularity of this exciting medium was to to tell the story in the form of a manga. Like many of the popular manga that have been translated into English, we are using the Japanese page and panel order. Japanese writing reads from right to left, so pages and panels are sequenced in what seems like reverse order to Western readers.
You can read the guide online or download it in a pdf format. I suggest you download it for easy reading and reference.
Link to the Wired Magazine article.