Does language define our identity?

I recently saw an ad for Chrysler in a magazine; a double page spread where the right page had a picture of a car and the left page read: "When you've been through hell, you tend to appreciate heaven." I thought it was pretty relevant since we had already talked about a previous Chrysler ad, and the significance of the slogan "imported from Detroit." I think especially in this case that language shapes the identity of the company. The slogan in particular paints a picture of a luxury car company coming from a place not often known as anything near luxurious. Without said slogan, people might associate the company with the city it is from, therefore ignoring that Chrysler wants to be known less as a car company and more as a lifestyle with struggles and achievements, rewarded by a nice car.
Outside of the magazine ad, I've noticed that people who fit certain stereotypes tend to speak differently than others. For example, my brother - a student at a liberal arts college, in the writing program - tends to sound somewhat ostentatious when he speaks, trying to incorporate bigger, fancier words to try to distinguish himself from his former high school counterpart. The effort that he puts into his language is obvious and he's even told me he does it to make himself seem more like a writer.