Kazimierz Leski, nom de guerre Bradl (21 June 1912 — 27 May 2000), was a Polish engineer, co-designer of the Polish submarines ORP Sęp and ORP Orzeł, a fighter pilot, and an officer in the World War II Home Army's intelligence and counter-intelligence.

He is credited, during World War II, with at least 25 journeys across German-held Europe, usually in the uniform of a Wehrmacht Major General.

After the war, he was imprisoned by Poland's communist authorities. He spent seven years on death row before being rehabilitated in 1956. He then resumed work as an engineer.

Kazimierz Leski was born in Warsaw on June 21, 1912. His father, Major Juliusz Leski, had been an engineer and a pioneer of Poland's arms industry. following the Polish-Bolshevik War. However, he fell out of grace after the May 1926 Coup d'État, when he remained loyal to the government. Because of that, Kazimierz had to work as a railway worker to pay for his studies at the Wawelberg and Rotwand College in Warsaw. He also got a simple job in the foundry of the Pocisk munitions works. To study professional books, he learned English, Russian and German—abilities that proved invaluable later. Early on, he also learned French.

Kazimierz (Polish pronunciation: [kaˈʑimjɛʂ]; Latin: Casimiria; Yiddish: קוזמיר) is a historical district of Kraków (Poland), best known for being home to a Jewish community from the 14th century until the Second World War.

The district of Kazimierz in Krakow is defined by the old shores of an island in the Vistula river. The northern branch of the river (Stara Wisła - Old Vistula) was filled in at the end of the 19th century, connecting Kazimierz with Krakow proper.

Three early medieval settlements are known to have existed on the island. The most important of these was the pre-Christian Slavic shrine at Skałka (“the rock”) at the western, upstream tip of the island. This site, with its sacred pool, was later Christianised as the Church of St. Michael the Archangel in the 11th century and was the legendary site of the martyrdom of St. Stanisław. There was a nearby noble manor complex to the southeast and an important cattle-market town of Bawół, possibly based on an old tribal Slavic gród, at the edges of the habitable land near the swamps that composed the eastern, downstream end of the island. There was also a much smaller island upstream of Kazimierz known as the “Tartar Island” after the Tartar cemetery there. This smaller island has since washed away.