The article discusses the fiftieth anniversary of the Polish Historical Institute in Rome, which was founded by Fr. Walerian Meysztowicz in 1945. Meysztowicz, a humanist and scientist, was then in Rome as a counselor of the Polish embassy to the Holy See. After the end of World War II, he decided to create an institution that would promote Polish science and culture in the West. Financing for the project was provided by the Lanckoroński Foundation from Brzezie, and the president of the Institute was prof. Karolina Lanckorońska. The Institute began its activity by organizing lecture meetings, which were aimed at gathering Polish scientists and maintaining contact with Polish science. In 1986, the Institute began editing materials related to the activities of the apostolic nunciature in Poland. In addition, the Lanckoroński Foundation provided scholarship support for research workers, enabling them to conduct research abroad. The Institute was also involved in popularization activities, such as Polish history courses for Poles at the high school level and celebrations of religious and national anniversaries. In recent years, the Institute has continued its scientific activities, cooperating with the Polish Academy of Sciences in Krakow to publish materials related to the Polish nunciature. All projects demonstrate the Institute's significant contribution to promoting Polish science and culture internationally.