In 1867, Fyodor Tyutchev, a Russian poet, diplomat and member of His Imperial Majesty's Own Chancellery, introduced the actual term of "russophobia" in a letter to his daughter Anna Aksakova on 20 September 1867, where he applied it to a number of pro-Western Russian liberals who, pretending that they were merely following their liberal principles, developed a negative attitude towards their own country and always stood on a pro-Western and anti-Russian position, regardless of any changes in the Russian society and having a blind eye on any violations of these principles in the West, "violations in the sphere of justice, morality, and even civilization". He put the emphasis on the irrationality of this sentiment. Tyuchev saw Western anti-Russian sentiment as the result of misunderstanding caused by civilizational differences between East and West. Being an adherent of Pan-Slavism, he believed that the historical mission of Slavic peoples was to be united in a Pan-Slavic and Orthodox Christian Russian Empire to preserve their Slavic identity and avoid cultural assimilation; in his lyrics Poland, a Slavic yet Catholic country, was poetically referred to as Judas among the Slavs. The term returned into political dictionaries of the Soviet Union only in the middle 1930s. Further works by Russian academics, such as Igor Shafarevich's "Russophobia" or the treaty from the 1980s attributed the spread of russophobia to Zionists.