Jan Teodor Kaszowski h. Janina

Castellan of Czernihów (Present day Chernihiv, Ukraine).

Chernihiv (Ukrainian: Черні́гів, translit. Černihiv [t%CA%83%C9%9Br%CA%B2%CB%88n%CA%B2i%C9%A6iu%CC%AF]; Russian: Черни́гов, translit. Černigov [t%C9%95%C9%AAr%CA%B2%CB%88n%CA%B2i%C9%A1%C9%99f]; Belarusian: Чарні́гаў, translit. Čarnihaŭ [%CA%88%CA%82ar%CB%88n%CA%B2i%C9%A3au%CC%AF]), a historic city in northern Ukraine, serves as the administrative center of the Chernihiv Oblast (province), as well as of the surrounding Chernihiv Raion (district) within the oblast. Administratively, it is incorporated as a city of oblast significance.

Chernihiv stands on the Desna River to the north-north-east of Kiev.

The Savior Transfiguration Cathedral of Chernihiv (1030s) is the oldest in Ukraine. Chernihiv was first mentioned in the Rus'-Byzantine Treaty (907) (as Черниговъ (Chernigov)), but the time of establishment is not known. According to the items uncovered by archaeological excavations of a settlement which included artifacts from the Khazar Khaganate, it seems to have existed at least in the 9th century. Towards the end of the 10th century, the city probably had its own rulers. It was there that the Black Grave, one of the largest and earliest royal mounds in Eastern Europe, was excavated in the 19th century.

In the southern portion of the Kievan Rus' the city was the second by importance and wealth. From the early 11th century it was the seat of powerful Grand Principality of Chernigov, whose rulers at times vied for power with Kievan Grand Princes, and often overthrew them and took the primary seat in Kiev for themselves. The grand principality was the largest in Kievan Rus and included not only the Severian towns but even such remote regions as Murom, Ryazan and Tmutarakan. The golden age of Chernihiv, when the city population peaked at 25,000, lasted until 1239 when the city was sacked by the hordes of Batu Khan, which started a long period of relative obscurity.

The area fell under the Grand Duchy of Lithuania in 1353. The city was burned again by Crimean khan Meñli I Giray in 1482 and 1497 and in the 15th to 17th centuries it changed hands several times between Lithuania, Muscovy (1408–1420 and from 1503), and the Polish-Lithuanian Commonwealth (1618–1648), where it was granted Magdeburg rights in 1623 and in 1635 became a seat of Chernihiv Voivodeship. The area's importance increased again in the middle of the 17th century during and after the Khmelnytsky Uprising. In the Hetman State Chernihiv was the city of deployment of Chernihiv Cossack regiment (both a military and territorial unit of the time).

Under the 1667 Treaty of Andrusovo the legal suzerainty of the area was ceded to Tsardom of Russia, with Chernihiv remaining an important center of the autonomous Cossack Hetmanate. With the abolishment of the Hetmanate, the city became an ordinary administrative center of the Russian Empire and a capital of local administrative units. The area in general was ruled by the Governor-General appointed from Saint Petersburg, the imperial capital, and Chernihiv was the capital of local namestnichestvo (province) (from 1782), Malorosiyskaya or Little Russian (from 1797) and Chernigov Governorate (from 1808).