Born in Kapina near Anglona (now Latvia) on 12 October 1913. His parents worked at Michał Reutt’s estate in Kapina. After the mobilization to the tsarist army in 1914 his father did not return from the front. His family moved to his grandparents in Rozentova, where Michał Bartoszewicz started learning at a Russian school. In 1925, Michał Bartoszewicz moved to Riga, where he finished a Polish primary school in 1932 and passed his exams to the secondary school. At the same time, he started working as a worker in typography. Between 1936 and 1940, he was a member of the Polish scout group in the Latvian Scouting. In 1937, he passed his secondary-school leaving exams and was enlisted in military service, which he did by 1939. In the same year he joined the Union of Poles in Latvia and became a delegate to the General Meeting in Daugavpils. He took up a job of a clerk at the Polish Consulate in Riga. After the outbreak of World War II he was enlisted into the Latvian army. Released in December the same year he started working as a technician trainee at the “Peteris Berzińsz” electrotechnical plant. In 1942, he joined the Polish Home Army. In October 1943, he was arrested by Gestapo and sent to the central prison in Riga. In September 1944, he was transported to the Stutthof camp, and from January through March 1945 was kept at the camp in Rybno near Wejherowo. After the liberation of the camp he was detained by Smersh, imprisoned and then mobilized to an infantry regiment of the Konstantin Rokossovski 1st Byelorussian front. In April 1945, he was wounded during the crossing of the Odra River. After a serious surgery at a hospital in Warsaw he was transported to Nizhny Novgorod for further treatment. When he recovered he started working at a kolkhoz near Mednoye and then Bologoye. After an amnesty he returned to Riga where he studied at the Technical University between 1946 and 1950. From 1954 he worked as a member of television transmitter support staff and from 1976 until his retirement – at a laboratory. As a pensioner he worked for the “Melodia” plant and the Music Academy at the technical teaching aids department. From the 1970s he has been involved in the activity of Polish communities in Latvia – from 1978 he was member of the “Polonez” Club, from 1988 of the Polish Cultural and Educational Society, and from 1989 of the Union of Poles in Latvia. In 1993, he became president of the board of the Union’s Riga Branch. Between 1996 and 2000, he edited the Polak na Łotwie [Pole in Latvia] magazine. At present, he is chief officer for war veterans and the repressed. Since 1995 he has been honorary member of the Union of Poles in Latvia.