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It was definitely an explicit goal. There's a great book on the topic: https://www.amazon.com/The-Chosen-Admission-Exclusion-Prince...

Here's a quote from a summary:

> At one point, [Harvard President] Lowell wrote to a Harvard philosophy professor to explain that enrolling a high number of Jewish students would "ruin the college" by causing elite Protestant students to attend other schools, according to Karabel's book. Harvard would be ruined "not because Jews of bad character have come; but the result follows from the coming in large numbers of Jews of any kind, save those few who mingle readily with the rest of the undergraduate body," Lowell wrote in the letter.

http://www.businessinsider.com/the-ivy-leagues-history-of-di...

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