Lake Oswego, Oregon is a suburb of Portland, Oregon. It is located about ten miles south of Portland, and has a population of around 37,000 people. The city is located on the west side of the Willamette River, in the Tualatin Mountains, a line of hills that runs along the west side of the Willamette. In the center of the city lies the eponymous lake, a semi-artificial lake. The city and lake were both named after the town of Oswego, New York, where an early resident had lived.

Founded in the mid-1800s, the initial success of the town came from iron smelting, quite unusual given its later history. Alas, Portland, Oregon was never fated to be a center of heavy industry, and Lake Oswego doubly so. In the early 1900s, the iron industry died out, and the city converted into what it is today, a bedroom community. But not just any bedroom community: I will let the City's official page describe it:

This gave rise to Oswego's reputation as a community of fine homes for people with taste.
Today, Lake Oswego is considered one of the finest residential communities in Oregon.
By reputation, for the past fifty years or more, Lake Oswego is the richest suburb of Portland. Some of the Portland area's biggest and most fancy homes are built around the shores of Lake Oswego, or on the high hills around town. Lake Oswego is also very scenic: more than most of the Portland area's suburbs, it has maintained its original forest cover. Lake Oswego has also resisted much of the sprawl that has covered other area suburbs.

In the Portland area, Lake Oswego has immediate connotations of "rich" and "snotty". Some of that is warranted, the median household income in Lake Oswego is $81,000, as opposed to Portland proper's $49,000. However, neighboring West Linn actually has a higher median income. So does Sherwood, a town so non-descript most Portlanders couldn't find it on a map. Yet neither one of these towns has the connotations that Lake Oswego has.

Lake Oswego is an attractive, upper-middle class suburb that has a reputation for being snotty, egotistical and exclusive that is not based on the actual statistical facts about the income level in the city. It is not alone in being a geographical location that has received hyperbolic connotations, but it is one of the ones I am most familiar with.

Lake Oswego's official history page: http://www.ci.oswego.or.us/library/brief-history-our-city
Census information on Lake Oswego: http://quickfacts.census.gov/qfd/states/41/4140550.html