|Gmina||Kolno (urban gmina)|
|• Mayor||Andrzej Duda|
|• Total||25.08 km2 (9.68 sq mi)|
|• Density||430/km2 (1,100/sq mi)|
|Time zone||CET (UTC+1)|
|• Summer (DST)||CEST (UTC+2)|
|Area code(s)||+48 086|
Kolno[ˈkɔlnɔ] is a town in northeastern Poland, located in the Podlaskie Voivodeship, about 150 km northeast of Warsaw. It is the seat of Kolno County, and the seat of the smaller administrative district (gmina) called Gmina Kolno, but it is not part of this district, as the town has gmina status in its own right. Kolno has 10,730 inhabitants (2007).
Kolno was first mentioned in 1222. The town first belonged to the Masovian Dukes, and then to the Polish crown. Kolno received city rights from Prince Janusz III of Masovia in 1425. The major economic expansion took place in the 16th century, with more trade and crafts. Kolno was destroyed by fire during the Kościuszko Uprising (1794). After the Partitions of Poland (1795) it became part of Prussia, till 1807, and subsequently, part of Duchy of Warsaw (Księstwo Warszawskie). From 1815 it belonged to Congress Poland (Królestwo Polskie). Kolno was destroyed again in the First World War, during battle between Russian and German empires. The population of Kolno during the interwar period increased to 5,163 persons, 70% of them Jewish.
Following the Nazi German and Soviet Invasion of Poland in World War II Kolno was taken over by the German forces on 8 September 1939. On 29 September Soviets enter the area in accordance with the Ribbentrop-Molotov Pact. The town remained in Soviet hands until Operation Barbarossa (22 June 1941) when it was overrun again by the Wehrmacht. In August 1941, nearly the entire Jewish population of Kolno was executed by the SS Einsatzgruppe killing squads into mass graves around the nearby villages of Kolimagi and Mściwuje. These mass executions took place in 3 actions, with the final one taking place early August 1941, when only 90 of the original 2000 plus Jews remained. Dina Chludniewicz, 21 at the time, was the only Jew in Kolno to survive the last action, when she ran for the woods, surviving a hail of machine gun fire. She survived the war and married a Neach Kancepolski from Slonim and emigrated to Australia.
The first 16 victims, accused of collaboration with the Soviets, were murdered by the Nazis on 15 July 1941 and buried at the Jewish cemetery together with the statue of Lenin erected by the NKVD.
Polish historian and cartographer Joachim Lelewel (1786–1861) was the first to gather all available mentions of Jan of Kolno known as Johannes Scolnus, and claimed that Scolvus was really Jan z Kolna (English: John of Kolno), a Polish navigator of the Danish fleet. He also found mentions of a Joannis de Colno who studied at the Kraków Academy in 1455, and a Colno or Cholno family of merchants and sailors living in Gdańsk.
Maria Lani was born in Kolno in 1895. In the late 1920s in Paris she was portrayed in paintings and sculpture by over fifty artists, including Bonnard, Chagall, Cocteau, Derain, Matisse, and Rouault.
- Orzeł Kolno - football club
- "Polin - dziedzictwo polskich Żydów. Kolno - info." Fundacja Ochrony Dziedzictwa Żydowskiego accessed 18.06.2010. 
- Wirtualny Sztetl. Kolno - historia. Muzeum Historii Żydów Polskich accessed 18.06.2010.
- Lackman, Jon (June–July 2014). "Maria Lani's Mystery". Art in America (New York: Brant Publications): 49–52.
- Kolno local government home page
- History of the Jewish community in Kolno by David Sotkowitz and Nathan Apkon