This week in history

May 27 1657: The Holy Roman Empire enters into an alliance with the Kingdom of Poland (Rzeczpospolita) and undertakes to provide military aid and act as an intermediary during the talks with Hetman Bohdan Khmelnytsky.

1821: An astronomical observatory is founded in Mykolaiv.

May 28 1982: Official festivities commemorating Kyiv’s 1,500th anniversary are held in the Soviet Ukrainian capital.

1997: Ukraine and the Russian Federation sign an agreement on the status of the Black Sea Fleet based on the territory of Ukraine, the terms and conditions of its stationing, delimitation parameters, and mutual settlements.

May 29 1922: The Council of People’s Commissars adopts a decree on the protection of green spaces in cities and other populated areas of the Ukrainian SSR.

1964: A new botanical garden measuring 180 hectares — one of the largest in the country — opens in Kyiv.

May 30 1923: The Ukrainian Historical-Philological Society is founded in Prague.

1997: During his visit to Ukraine President Boris Yeltsin of Russia signs the Treaty on Friendship, Cooperation, and Partnership.

May 31 1946: The Oleh Antonov Aircraft Design Bureau is established in Kyiv.

1989: The founding congress of the International Association for Ukrainian Studies takes place in Naples during a scholarly conference on the problems and prospects of Ukrainian culture.

June 1 1996: Ukraine delivers the rest of its missiles to Russia and becomes a nuclear-free country.

1996: Vienna resolves to accept Ukraine as a full-fledged member of the Central European Initiative.

June 2 1935: The Politburo and the Organizing Bureau of the Central Committee of the Communist Party (Bolsheviks) of Ukraine adopt a resolution on the activities of the Republican Society of Political Prisoners, whereupon this association is liquidated.

1990: The 1st All-Ukrainian Congress of the Union of Independent Ukrainian Youth is convened.