A unique category offered by some specialised online dating sites is that of international mail order bride services. The concept of these sites is really just a new take on an old idea, which is to find a bride from a distant land. As far back as 19th century America, it was common for men to write 'back East' to find a bride who would join them in 'the territories' as America expanded west across the North American continent. With most of the world populated, and with the popularity of the Internet, the idea has evolved, although the same basic purpose is served.