Short answers, pulled from the story.
Kraków lost its status as the capital of Poland in 1596, when Sigismund III of the House of Vasa moved the administrative capital of the Polish-Lithuanian Commonwealth to Warsaw. Kraków had served as the royal seat since 1038.
At the outbreak of World War II, approximately 56,000 Jews lived in Kraków, nearly one quarter of the city's population. By November 1939, that number had grown to around 70,000. The Kraków Ghetto was established in the Podgórze neighborhood in March 1941, and mass deportations to extermination camps including Auschwitz and Bełżec began in June 1942. The ghetto was finally liquidated in March 1943.
Kraków's Old Town was placed on the UNESCO World Heritage List in 1978 as one of the very first sites ever granted that status. It was recognised for its extensive medieval, Gothic, Renaissance, and Baroque architecture, including Wawel Castle, Wawel Cathedral, St. Mary's Basilica, and the largest medieval market square in Europe, Rynek Główny.
Karol Wojtyła served as cardinal archbishop of Kraków from 1964 to 1978. In 1978, the Catholic Church elevated him to the papacy as John Paul II, making him the first non-Italian pope in over 450 years. He spent the preceding two decades in Kraków successfully lobbying for permission to build churches in the newly industrialised suburb of Nowa Huta.
Jagiellonian University was founded in 1364 by King Casimir III the Great as Studium Generale, making it the second oldest university in central Europe after Charles University in Prague. It was renamed in 1817 to honour the royal Jagiellonian dynasty. Famous alumni and figures connected to the university include Nicolaus Copernicus and Pope John Paul II.
A trumpet call called the hejnał mariacki is sounded every hour from St. Mary's Basilica in Kraków's Market Square. The melody ends abruptly in mid-note, according to tradition commemorating a medieval guard who was shot by a Mongol archer while sounding the alarm during an invasion. The legend was retold in Eric P. Kelly's 1928 book The Trumpeter of Krakow, which won a Newbery Award.