structural:scholar_edition, information:highlighting, structural:summarization
Novgorodians

Pomors were soon followed by tribute collectors from the Novgorod Republic, and the Kola Peninsula gradually became a part of the Novgorodian lands. A 1265 treaty of Yaroslav Yaroslavich with Novgorod mentions Tre Volost (волость Тре), which is later also mentioned in other documents dated as late as 1471. In addition to Tre, Novgorodian documents of the 13th–15th centuries also mention Kolo Volost, which bordered Tre approximately along the line between Kildin Island and Turiy Headland of the Turiy Peninsula. Kolo Volost lay to the west of that line, while Tre was situated to the east of it.

By the 13th century, a need to formalize the border between the Novgorod Republic and the Scandinavian countries became evident. The Novgorodians, along with the Karelians who came from the south, reached the coast of what now is Pechengsky District and the portion of the coast of Varangerfjord near the Jacob's River, which now is a part of Norway. The Sami population was forced to pay tribute. The Norwegians were also attempting to take control of these lands, resulting in armed conflicts. In 1251, a conflict between the Karelians, Novgorodians and the servants of the king of Norway led to the establishment of a Novgorodian mission in Norway. Also in 1251, the first treaty with Norway was signed in Novgorod regarding the Sami lands and the system of tribute collections, making the Sami people pay tribute to both Novgorod and Norway. By the terms of the treaty, Novgorodians could collect tribute from the Sami as far as the Lyngen fjord in the west, while Norwegians could collect tribute on the territory of the whole Kola Peninsula except in the eastern part of Tersky Coast. No state borders were established by the 1251 treaty.

The treaty led to a short period of peace, but the armed conflicts resumed soon thereafter. Chronicles document attacks by the Novgorodians and the Karelians on Finnmark and northern Norway as early as 1271, and continuing well into the 14th century. The official border between the Novgorod lands and the lands of Sweden and Norway was established by the Treaty of Nöteborg on August 12, 1323. The treaty primarily focused on the Karelian Isthmus border and the border north of Lake Ladoga.

Another treaty dealing the matters of the northern borders was the Treaty of Novgorod signed with Norway in 1326, which ended the decades of the Norwegian-Novgorodian border skirmishes in Finnmark. Per the terms of this treaty, Norway relinquished all claims to the Kola Peninsula. The treaty did not address the situation with the Sami people paying tribute to both Norway and Novgorod, and the practice continued until 1602. While the 1326 treaty did not define the border in detail, it confirmed the 1323 border demarcation, which remained more or less unchanged for the next six hundred years, until 1920.

In the 15th century, Novgorodians started to establish permanent settlements on the peninsula. Umba and Varzuga, the first documented permanent settlements of the Novgorodians, date back to 1466. Over time, all coastal areas to the west of the Pyalitsa River had been settled, creating a territory where the population was mostly Novgorodian. Administratively, this territory was divided into Varzuzhskaya and Umbskaya Volosts, which were governed by a posadnik from the area of the Northern Dvina. The Novgorod Republic lost control of both of these volosts to the Grand Duchy of Moscow after the Battle of Shelon in 1471, and the republic itself ceased to exist in 1478 when Ivan III took the city of Novgorod. All Novgorod territories, including those on the Kola Peninsula, became a part of the Grand Duchy of Moscow.

The Novgorod Republic lost control of the peninsula to the Grand Duchy of Moscow in 1471, but the Russian migration did not stop. Several new settlements were established during the 16th century, and the Sami and Pomor people were forced into serfdom. In the second half of the 16th century, the peninsula became a subject of dispute between the Tsardom of Russia and the Kingdom of Denmark–Norway, which resulted in the strengthening of the Russian position. By the end of the 19th century, the indigenous Sami population had been mostly forced north by the Russians as well as by newly arriving Izhma Komi and Kominized Nenets (so-called Yaran people), who migrated here to escape a reindeer disease epidemic in their home lands in the southeast of the White Sea. The original administrative and economic center of the area was Kola, situated at the estuary of the Kola River into the Kola Bay. In 1916, Romanov-na-Murmane (now Murmansk) was founded and quickly became the largest city and port on the peninsula.