54 families of craftsmen were invited to the city from German principalities and settled in the newly established German Sloboda neighborhood with about 50 clay-made houses. In 1810 there were 8,328 people living in Poltava; that same year, the city's first theater was built. In August 1812, on orders of Little Russia Governor General Lobanov-Rostovsky, the famed Ukrainian writer and statesman Ivan Kotlyarevsky formed the 5th Poltava Cavalry Cossack Regiment. By 1860, Poltava had around 30,000 inhabitants, a district school, a gymnasium, an Institute for Noble Maidens, a spiritual academy, a cadet corps, a library and a number of schools. In 1870 a railway station was opened, leading to rapid economic growth in the region. However, by 1914 the Population of Poltava (around 60,000) was mostly working in small enterprises. In the late 19th and early 20th centuries Poltava became an important cultural centre, where many representatives of Ukrainian national revival were active. 20th century During the events of 1917–1920, Poltava was under the rule of a number of governments, including the Central Rada, Hetmanate, Ukrainian People's Republic, White Movement and Bolsheviks. From 1918 to 1919 there was Occupation of Poltava by the Bolsheviks. After becoming a part of Ukrainian Soviet Socialist Republic, Poltava experienced accelerated industrial growth, and its population increased to 130,000 by 1939. In World War II, the Nazi Wehrmacht occupied Poltava from 18 September 1941 until 23 September 1943, when it was retaken during the Chernigov-Poltava Strategic Offensive of the Battle of the Dnieper. During the Nazi occupation the Jewish population (9.9% of the total population in 1939) was imprisoned in a ghetto before being murdered during mass executions perpetrated by an Einsatzgruppe and buried in mass graves in the area. By the summer of 1944, the United States Army Air Forces conducted a number of shuttle bombing raids against Nazi Germany under the name of Operation Frantic. Poltava Air Base, as well as Myrhorod Air Base, were used as eastern locations for landing B-17 Flying Fortress heavy bombers involved in those operations. The post-war restoration of Poltava continued in the 1950s and 1960s. The city became an important centre of military education in the Soviet Union, where missile and communications officers were prepared, and was also home to a Soviet Air Force division of heavy bombers. Geography Climate Poltava has a warm-summer humid continental climate (Köppen: Dfb), with four distinct seasons, it is one of