Principality of Pskov

The Principality of Pskov (Russian: Псковское княжество, Pskovskoye knyazhestvo) or Lordship of Pskov (государство Псковское) was a medieval state that grew out of the Rus' Khaganate in the late 9th century. The city of Pskov was founded by the Rus', then expanded into a duchy or principality. It was a vassal state of various Rus' states between the 1230s and 1348, when the Treaty of Bolotovo recognized the independence of Pskov (known in historiography henceforth as the Pskov Republic); it then came under protection of the Grand Duchy of Moscow.

Pskov is situated on the southern shore of the Lake Peipus, to the east of Livonia, and to the west of Novgorod. In the 13th century, the Principality of Pskov was a narrow strip of land along the eastern Narva River and Peipus, bordered to the south by the Velikaya River basin. The division between Livonia and Pskov was made up by an area of water bodies and poorly settled areas.

The town of Pskov was founded in the late 9th century by the Rus'. Olga of Kiev, the wife of Igor of Kiev, was born in Pskov. In 1065–67, Vseslav attacked Pskov and Novgorod, then was captured by Iziaslav I of Kiev and his two brothers and imprisoned in Kiev.

In 1218, the princes of Novgorod and Pskov attacked Estonia and Latvia, while the Lithuanians had attacked Pskov in the meantime. A conflict ensued in the following years between Pskov and Letgallia. Pskov invaded Livonia in 1221.

The Novgorod Chronicle mentions the campaign Yaroslav Vsevolodovich of Novgorod in 1228; Yaroslav led his army against Pskov, upon which the inhabitants sealed the city and refused to let Yaroslav in. There were rumours that Yaroslav now wanted to imprison Pskov's most notable men, but Yaroslav declared that he had good intentions, wanting to deliver gifts, and now assembled an army and to attack Riga. Now, Pskov entered a military alliance with Riga. The Novgorod nobility believed that Yaroslav had merely used the pretext of attacking Riga to conquer Pskov. Yaroslav now asked Pskov to take part in the attack, but Pskov refused.

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