“O’ Pickels”

Where did the concept of a pickle originate from? ( I happen to have finished a homemade pickle and conversation about how great they are right before I returned to read the paragraph that discussed them so I needed to ask a question on them)

Americanization:

When was there a seemingly conscious effort on Americanization? Did they believe in cultural superiority, only want to make immigrants familiar with American ways, believe that there was an practical advantage of following American culture in America, or some other reason? It appears there was much effort spend on this process, but what was the ideology behind it?