Short answers, pulled from the story.
Leningrad Oblast is a federal subject of Russia, an oblast covering 84,500 square kilometers with a population of 2,000,997 at the 2021 census. Its administrative center and largest city is Gatchina, and the region is highly industrialized.
The city of Leningrad restored its original name, Saint Petersburg, after a referendum in 1991, but the surrounding oblast kept the name Leningrad.
Leningrad Oblast was established on the 1st of August 1927, though its borders were not mostly settled in their present position until 1946.
Aleksandr Yuryevich Drozdenko has been governor of Leningrad Oblast since being appointed on the 28th of May 2012. The first governor was Vadim Gustov, who served from 1996 to 1998.
Leningrad Oblast borders Finland's Kymenlaakso and South Karelia regions to the northwest and Estonia's Ida-Viru County to the west. It also borders five Russian federal subjects: the Republic of Karelia, Vologda Oblast, Novgorod Oblast, Pskov Oblast, and the federal city of Saint Petersburg.
Leningrad Oblast became the site of the Battle of Leningrad after Germany invaded the Soviet Union in Operation Barbarossa in 1941. Wehrmacht forces captured its southwestern part and reached Tikhvin, while Finnish troops recaptured the Karelian Isthmus and encircled Leningrad until Soviet offensives in 1944 forced Finland to cede the isthmus again under the Moscow Armistice of the 19th of September 1944.