He was born on 6 May 1882 in the village of Krassowo Wielkie, Wysokie Mazowieckie. From 1900 he studied at the Faculty of Physics and Mathematics at the University of Warsaw, and from 1901 also at the Faculty of Chemistry at the Warsaw Polytechnic Institute. In the years 1905-1908 he studied in Prague, where he was awarded the title of engineer at the Faculty of Chemistry of the local polytechnic. In 1909-1912 he was a student of the Agricultural College of Jagiellonian University, and then an assistant at the experimental plant there. He began independence activities already during his studies. From 1901, he was a member of the "Zet" organization, a year later he was a co-organizer of the Jan Kiliński Union, and in 1906 the National Workers' Union. In 1915 (from September to December) he served in the 1st Regiment of Polish Legions. In the same year he participated in the work of the Supreme Committee of the United States Independence Party. In 1920, he was one of the co-founders and members of the authorities of the National Workers' Party On its behalf, he was a member of the Sejm of the Republic of Poland and a councilor of Warsaw, in the years 1928-1935. He also held managerial functions in administration - at the Ministry of Agricultural Reforms and at the Ministry of Labor and Social Welfare. In 1937, he joined the Democratic Club in the capital, and then the Labor Party.

He was active in the ranks of the underground conspiracy (Union of Armed Struggle) as well as the underground structures of the Labour Party since 1941. He was the director of the Department of Labor and Social Welfare in the Government Delegation for the Country, and the deputy government delegate from December 1942. After being arrested by the Gestapo, Professor J. Piekałkiewicz was approved on 21 April 1943 by the Prime Minister General W. Sikorski and the President of the Republic of Poland W. Raczkiewicz as a government delegate. As of 3 May1944, this was synonymous with the function of the deputy prime minister of the Polish government in exile. On 13 July 1944, in agreement with the Home Army commander, he made the decision on the breakout of the Warsaw Uprising. After its fall, he got out of the city and continued his independence activities.

He was detained by the NKVD as a result of the Pruszków provocation on 27 March  1945, and then transported to Moscow along with other 16 leaders of the Polish Underground State and sentenced unlawfully to 8 years in prison. Two weeks before his release on 13 March 1953, he was most likely murdered by officers of the security apparatus in the prison in Włodzimierz at Klaźma.

He was born on 7 July  1898 in Waśniewo (Mława Poviat). He graduated from teacher's studies in Warsaw in 1918. In the years 1917-1918, a member of the Polish Military Organization. In November 1918, he voluntarily joined the Polish Army. He took part in disarming the Germans in Warsaw. He participated in the Polish-Bolshevik war in the ranks of the 31st Strzelców Kaniowskich Infantry Regiment. He was seriously wounded on 2 August 1920. He held various commanding functions in the interwar period.

At the end of August 1939, he was appointed commander of the 4^th Infantry Division Backup Center in Rzeszów. He evacuated to Hungary, where he was interned. He escaped from the camp twice. At the beginning of January 1940 he arrived in France. He joined the Polish Armed Forces. He took the position of the battalion commander in the 4th Infantry Division. After the fall of France, he evacuated to Great Britain. At the beginning of 1941, he volunteered to serve the country. He was transported to Poland on the night of 6-7 January 1942. In February of the same year he was assigned to the Retaliation Union as a training officer. In December 1942, he assumed the position of the Head of Division IV (training) of the Kedyw Directorate for Subversion of the Home Army. He organized a school of sabotage, under the code name Zagajnik ("Grove"). As of August 1943, he had managed the Central Supply Center codenamed "Clock", "Stadium" serving the districts of Volhynia, Polesie and Nowogródek. In May 1944 he was appointed commander of the Home Army District in Polesie. During the "Burza" campaign, he commanded the 30th "Poleska" Infantry Division of the Home Army. At the end of July 1944, due to the threat from the Soviets, he ordered this unit to be dissolved. Some of his subordinates, who managed to get to the vicinity of Warsaw, were disarmed by the NKVD and taken to the Majdanek camp, and from there to the Soviet labuor camps. Krajewski himself moved to Otwock near Warsaw, where he made contact with the local Home Army underground.

He was arrested by the NKVD on 11 December  1944 and underwent a very difficult investigation (his ribs were broken as a result of torture). He was sentenced by the Military Garrison Court in Warsaw on 23 April , 1945 to 10 years in prison. He was released on 28 July , 1945 at the Bąkowiec station during transport to the prison in Wronki by former Home Army units. He exposed himself during the amnesty in August 1945. He died in Wołomin on 16 December 1 1989. He was decorated with the Virtuti Militari Cross, twice with the Cross of Valour, the Silver Cross of Merit.

He was born on 26 August  1883 in Ternopil into a Polish-Ukrainian family. In 1905 he started studying at the Law Faculty of the University of Lwów, but he did not graduate. Since 1904 he was associated with the Polish Socialist Party, since 1906 with the PPS - the Revolutionary Faction. In April 1911 he was arrested by the Russians for his independence activities and sentenced to 8 years in prison. He served his sentence in the Szlisselburg fortress until 1917. From 1919 he was a member of the Executive Committee of the Warsaw Council of Workers' Delegates, as well as the Supreme Council and the Central Executive Committee of the PPS. During the Polish-Bolshevik war, he was the deputy chairman of the Warsaw Workers' Defense Committee. In the period from 1921 to 1939, he remained the secretary general of the PPS. He was also a deputy to the Sejm of the Republic of Poland (in 1919-1935).

He was active in the underground conspiracy from October 1939 - as the secretary general of the PPS-WRN (Freedom - Equality - Independence), from November 1939 also as the chief commander of the PPS People's Guard. In the period from February 1940 to September 1941 and from March 1943 to March 1945, on behalf of the PPS, he was the chairman of the underground parliament - the Political Conciliation Committee, and then the National Political Representation and the Council of National Unity. He was arrested by the NKVD as a result of the Pruszków provocation on 27 March1945. He was taken to Moscow together with 16 other leaders of the Polish Underground State and unlawfully sentenced to 1.5 years in prison. He was released in November 1945, he returned to Poland, where he resumed independence activities as part of the underground National Center of PPS-WRN.

He was arrested by the UB on 16 May  1947 and sentenced on 19 November 1948 by the Military District Court in Warsaw to 10 years imprisonment. He was murdered by one of the prison guards in Rawicz on 30 April  1950.

He was born on 1 March  1897 in Białe Wody in Ukraine. He took part in World War I in the ranks of the Russian army. In 1917 he graduated from an officers' school in Kiev. In the same year he joined the First Polish Corps, where he served, among others, in the Officer's Legion. After the Germans disarmed the corps at the end of 1918, he joined the Polish Army. He took part in the Polish-Bolshevik war in the ranks of the 1st Cavalry Regiment and 1st Infantry Division of Legions. In the years 1924–1925 he completed the course for younger cavalry commanders at the Cavalry Training Center in Grudziądz. In the years 1930-1934 he served in the Border Protection Corps as the commander of the "Iwieniec" Cavalry Squadron.

He took part in the rank of major in the defensive war of 1939 as a quartermaster and II deputy commander of the 11th Legionary Regiment. At the end of September, he was sent into German slavery near Krasnobród, from which he quickly escaped and began underground activities within the ZWZ. From November 1941, he was an inspector in the Eastern Sub-District of the Warsaw Area of the Home Army. On 8 August  1944, he took over the function of the commander of this structure after Colonel H. Suszczyński "Szeliga" was arrested by the NKVD.

He was arrested by the Soviet security apparatus on 23 December 1944. He was sentenced to death on 21 February  1945 by the Garrison Court in Warsaw and on murdered in the prison in 11 Listopada Street on 5 March  1945. His body was buried in an unknown location. He was awarded the Silver Cross of Merit, the Cross of the Brave