Question: In 1990, who became the president of the country that Germany invaded?

Knowledge 1: Gleiwitz incident
The Gleiwitz incident was a part of a larger operation carried out by Abwehr and SS forces. Other orchestrated incidents were conducted along the Polish-German border at the same time as the Gleiwitz attack, such as a house burning in the Polish Corridor and spurious propaganda. The project was called Operation Himmler and comprised incidents giving the appearance of Polish aggression against Germany. German newspapers and politicians, including Adolf Hitler, had made accusations against Polish authorities for months before the 1939 invasion of organising or tolerating violent ethnic cleansing of ethnic Germans living in Poland. On 1 September 1939, the day following the Gleiwitz attack, Germany launched Fall Weiss (Case White) the invasion of Poland, which precipitated World War II in Europe. Hitler cited the border incidents in a speech in the Reichstag on the same day, with three of them called very serious, as justification for his invasion of Poland. Hitler had told his generals on 22 August, "I will provide a propagandistic casus belli. Its credibility doesn't matter. The victor will not be asked whether he told the truth". [SEP] Knowledge 2: 1990 Polish presidential election
The leader of the Solidarity movement, Lech Wałęsa, won the first round. However, he did not earn over 50% of the vote, which led to a runoff election. Wałęsa faced Polish - Canadian businessman Stanisław Tymiński in the second round, defeating him easily.
Knowledge 1: East Germany–West Germany football rivalry
On national team level West Germany played its first post-war international on 22 November 1950 against Switzerland in Stuttgart, while East Germany played their first game against Poland on 21 September 1952 in Warsaw and its 293rd and last on 12 September 1990 against Belgium in Brussels. The two sides met just once on senior national team level, on 22 June 1974, in a group game of the 1974 FIFA World Cup, held in West Germany. The game in Hamburg, in front of 62,000, was won 1 -- 0 by the guest team courtesy to a goal by Jürgen Sparwasser. East Germany finished the tournament in sixth place while West Germany won the FIFA World Cup. For the East it was the only participation while the West won the 1954 and 1990 editions as well. The two countries never met again at this level despite West Germany frequently requesting a rematch but the East declining, despite strong interest from East German players, coaches and fans. With the German reunification a special game between the two former countries was planned for 21 November 1990 in Leipzig but was cancelled after a fatal shooting of a supporter at a game between FC Sachsen Leipzig and FC Berlin by the police on 3 November. West and East Germany had been drawn against each other for the qualifying of the 1992 UEFA European Football Championship but the latter was withdrawn because of the German reunification. [SEP] Knowledge 2: 1990 Polish presidential election
The leader of the Solidarity movement, Lech Wałęsa, won the first round. However, he did not earn over 50% of the vote, which led to a runoff election. Wałęsa faced Polish - Canadian businessman Stanisław Tymiński in the second round, defeating him easily.
Knowledge 1: Gleiwitz incident
The Gleiwitz incident was a part of a larger operation carried out by Abwehr and SS forces. Other orchestrated incidents were conducted along the Polish-German border at the same time as the Gleiwitz attack, such as a house burning in the Polish Corridor and spurious propaganda. The project was called Operation Himmler and comprised incidents giving the appearance of Polish aggression against Germany. German newspapers and politicians, including Adolf Hitler, had made accusations against Polish authorities for months before the 1939 invasion of organising or tolerating violent ethnic cleansing of ethnic Germans living in Poland. On 1 September 1939, the day following the Gleiwitz attack, Germany launched Fall Weiss (Case White) the invasion of Poland, which precipitated World War II in Europe. Hitler cited the border incidents in a speech in the Reichstag on the same day, with three of them called very serious, as justification for his invasion of Poland. Hitler had told his generals on 22 August, "I will provide a propagandistic casus belli. Its credibility doesn't matter. The victor will not be asked whether he told the truth". [SEP] Knowledge 2: Mátyás Szűrös
Mátyás Szűrös (Hungarian pronunciation: [ˈmaːcaːʃ ˈsyːrøʃ]; born 11 September 1933 in Püspökladány) is a Hungarian politician. He served as provisional President of the Republic from 23 October 1989 to 2 May 1990. His presidency occurred during Hungary's transition from Communism to democratic government.Szűrös served as Speaker of the National Assembly of Hungary from March 1989 to May 1990. In the fall of 1989, as part of an agreement between the Communists and the opposition to establish multiparty democracy, the 1949 Constitution was almost completely rewritten to remove its Communist character. The Presidential Council, the country's Communist-era collective presidency, was dissolved. Under the Constitution, Szűrös became provisional president until the election. Soon after taking office on 23 October he made the official proclamation that Hungary had removed the "People's Republic" from its constitutional name and was now the "Republic of Hungary."

Answer: Lech Wałęsa