The letter, written in 1934, speaks about Hitler and about Jewish refugees in America.
Einstein mentions his fellow German scientist Max Planck, and the audience he had reportedly held with Hitler in an attempt to dissuade him from dismissing all German Jewish scientists from their positions.
Einstein had already fled Germany the previous year and seemed to be critical of the American Jews he found himself surrounded with in his new country, saying that they "sabotage things out of fear; they give money and keep the people at a distance.”
The end of Einstein's letter focuses specifically on Hitler and the problems that were looming on the horizon for Europe's Jews.
He explains that the reason why he has not been outspoken in his criticism of Hitler is because "as a German resident and government employee for many years, as well as a Jew and someone robbed of his property by the Nazis, I cannot be an objective judge in the eyes of the general population.
"In this fight, Jews should really appear publicly as little as possible, because otherwise, opposition to Hitler’s Germany will be stamped as a Jewish affair and thereby weakened,” he concluded.
Although ultimately Einstein did become a vocal critic of Hitler's actions in Europe, and helped other German Jews apply for visas in order to escape Nazi rule, this letter offers interested parties a glimpse into how he perceived his own biases, and his hesitance to become the "face" of anti-Hitlerism before the outbreak of the Holocaust.
The letter is estimated to be worth over $20,000, and will be up for auction until May 20.