Tula Oblast in the context of "M4 highway (Russia)"

The Oka (UK: /ˈɒkə/, US: /ˈoʊkə/; Russian: Ока IPA: [ɐˈka]) is a river in central Russia, the largest right tributary of the Volga. It flows through the regions of Oryol, Tula, Kaluga, Moscow, Ryazan, Vladimir and Nizhny Novgorod and is navigable over a large part of its total length, as far upstream as the town of Kaluga. Its length is 1,500 km (930 mi) and its catchment area 245,000 km (95,000 sq mi). The Russian capital Moscow sits on one of the Oka's tributaries—the Moskva, from which the capital's name is thought to be derived.

The 163rd Rifle Division was formed as an infantry division of the Red Army just before the Second World War began, in the Tula Oblast, based on the pre-September 13, 1939 shtat (table of organization and equipment). As a reinforced rifle division, it took part in the Winter War with Finland, where it was encircled at Suomussalmi. Despite a rescue attempt by the 44th Rifle Division from the Raate Road (which was also the route used by some of the 163rd's forces) the division was largely destroyed in one of the best-known Finnish victories of the war.

What little remained of the 163rd was moved postwar to Novgorod in the Leningrad Military District to be rebuilt as a motorized division. At the outbreak of war with Germany it was assigned to 1st Mechanized Corps and was part of the reserves of the redesignated Northern Front. In common with most Soviet motorized divisions it was significantly short of trucks and its outdated tanks were lost, mostly to breakdowns, before the end of August. During that month, as part of 34th Army, it took part in the Northwestern Front's counterstrike at Staraya Russa which briefly surrounded two German divisions and inflicted a considerable delay on Army Group North's advance on Leningrad, although at heavy cost.

Moscow Oblast (Russian: Московская область, romanized: Moskovskaya oblastʹ, IPA: [mɐˈskofskəjə ˈobləsʲtʲ], informally known as Подмосковье, Podmoskovye, IPA: [pədmɐˈskovʲjə]) is a federal subject of Russia (an oblast). With a population of 8,524,665 (2021 Census) living in an area of 44,300 square kilometers (17,100 sq mi), it is one of the most densely populated regions in the country and is the second most populous federal subject. The oblast has no official administrative center; its public authorities are located in Moscow and Krasnogorsk (the Moscow Oblast Duma and the local government), and also across other locations in the oblast.

Located in European Russia between latitudes 54° and 57° N and longitudes 35° and 41° E, Moscow Oblast borders Tver Oblast in the northwest, Yaroslavl Oblast in the north, Vladimir Oblast in the northeast and east, Ryazan Oblast in the southeast, Tula Oblast in the south, Kaluga Oblast in the southwest, and Smolensk Oblast in the west. The oblast mostly surrounds the federal city of Moscow, which is not part of the oblast, but rather a separate federal subject in its own right. The oblast is highly industrialized, with the major industries being metallurgy, oil refining, and mechanical engineering, along with the food, energy, and chemical industries.

Tula (Russian: Ту́ла, IPA: [ˈtulə]) is the largest city and the administrative center of Tula Oblast in Russia, located 193 kilometers (120 mi) south of Moscow. Tula is located in the northern Central Russian Upland on the banks of the Upa River, a tributary of the Oka. At the 2010 census, Tula had a population of 501,169, an increase from 481,216 in 2002, making it the 32nd-largest city in Russia by population.

A primarily industrial city, Tula was a fortress at the border of the Principality of Ryazan. The city was seized by Ivan Bolotnikov in 1606 during the Time of Troubles and withstood a four-month siege by the Tsar's army. Historically, Tula has been a major centre for the manufacture of armaments. The Demidov family built the first armament factory in Russia in the city, in what would become the Tula Arms Plant, which still operates to this day.

The Battle of Kulikovo (Russian: Куликовская битва, romanized: Kulikovskaya bitva) was fought between the forces of Mamai, a powerful Mongol military commander of the Golden Horde, and Russian forces led by Grand Prince Dmitry of Moscow. The battle took place on 8 September 1380, at Kulikovo Field near the Don River (now Tula Oblast, Russia) and was won by Dmitry, who became known as Donskoy ("of the Don") after the battle.

Although the victory did not end Mongol domination over Russia, it is traditionally regarded as the turning point at which Mongol influence began to wane and Moscow's power began to rise. The battle would allow Moscow to strengthen its claims of ascendancy over the other Russian principalities, in which it would ultimately become the centre of a centralized Russian state..