of this party (until 1925). As a deputy of the Land of Wilno to the Polish Sejm, he was released from the military. Zyndram-Kościałkowski remained in the parliament until 1939. In the early 1920s, he was a member of a Freemason’s Lodge “Tomasz Zan”, and in April 1925, after abandoning Polish People's Party "Wyzwolenie", he co-created the so-called Parliamentary Labour Club (Klub Pracy, later renamed into Labour Party), together with Kazimierz Bartel. Zyndram-Kościałkowski did not play any significant role in the 1926 May Coup. As key member of the Labour Party, he supported the Sanacja movement, and in May 1927 became a member of the Warsaw City Council. At the same time, he was a deputy chairman of the Association of Army Reservists, and leading member of Association of Polish Cities. In the Parliament, he was responsible for the budget of the Ministry of Military Affairs for the year 1927/28. Following the 1928 Polish legislative election, Zyndram-Kościałkowski was again elected from the District of Wilno. In March 1928, he became deputy chairman of the Nonpartisan Bloc for Cooperation with the Government (BBWR), and in June, his Labour Party joined the BBWR, as autonomous organization. Zyndram-Kościałkowski was regarded as an avid supporter of Józef Piłsudski. In defence of his policies, in 1922, he challenged General Józef Haller to a duel. 1930s On 20 July 1930 Zyndram-Kościałkowski was named Voivode of Białystok Voivodeship, remaining there until late February 1934. He improved local administration, built sewer system and paved streets of Białystok. He also founded the unemployment committee and Agricultural Chamber. Due to his efforts, local entrepreneurs presented their products at the Northern Trade Fair in Wilno. Also, he was one of co-founders of sports club Jagiellonia Białystok. To honor his work, on 4 September 1935 Zyndram-Kościałkowski was named Honorary Citizen of Białystok, and a boulevard was named after him. Following the 1930 Polish legislative election, he was again elected to the Sejm (November 1930). On 28 June 1934, after Minister of Internal Affairs Bronisław Pieracki had been murdered by Ukrainian nationalists, Zyndram-Kościałkowski took over this post. As a minister, he tried to streamline local administration, and reach an agreement with moderate Ukrainian organizations. In the summer of 1935, Polish authorities reached a compromise with the Ukrainian National Democratic Alliance (UNDO), and as a result, the UNDO took place in the 1935 Polish legislative election. After the death of Józef Piłsudski (12 May