The first notations of the Nevalainen family are found in the Land Registers of Äyräpää and Suur-Jääski from the 15th century. At the time there were about 1000 houses or "smokes" in the Suur-Jääski parish. Persons with the name Nevalainen lived in three villages. The names and sizes of the villages were: Nevala, 3 houses, Joutseno, 22 houses and Pirhola, 6 houses. The count of Nevalainen's in each village does not appear in the documents. However, assuming ca 20 families would have been living on the Karelia isthmus, then the total number of family members might have been between 150 and 200. The ancestors of that crowd might have been living at those grounds for hundreds of years already. It is not known if they were all relatives to each other.

In the last centuries of the middle ages, the inhabitants of the isthmus made long hunting and fishing trips along the Saimaa water courses by boats. Some Nevalainen family members were certainly along on these trips.

Thus the water ways were already familiar when the 25-year war started out at the end of the 15th century, and a part of the inhabitants escaped towards the north. One part of the family died in the war, while another part managed to continue their living in the old places, and a third part moved to the town of Viipuri. Some of those people then continued further towards north, stopped at the vicinity of Lappeenranta, and settled there.

In the year 1617 there were four houses in Lappee and in Äyräpää five houses more by the name Nevalainen. A part of those headed towards north wandered through the whole Savo county as far as Pohjanmaa, without leaving any markings into the Land Registers of Savo. Families by the name Nevalainen are found at Kalajoki valley in the great parish of Saloinen.

An influental family of clergymen by the name Agander lived in Viipuri from the begining of the 16th century. They were descendants of a cavalry estate family in Jokioinen by the name Nevalainen. The family reverted later to being farmers and took back their earlier name. Even to this day many families named Nevalainen live around Lappeenranta and Imatra.

Nevalainen families arrived into northern Karelia from Pohjanmaa along the water ways of Oulunjoki, or alternatively through Northern Savo. Pekka Nevalainen, who can be found in the early land registers, lived in 1633 in Iisalmi, and two years later in 1637 he can be found in Savikylä in Nurmes. Pekka with his family is the first known Nevalainen in Northern Karelia. It might be that simultaneously some other Nevalainen families have moved to the area. From Nurmes the Nevalainen families have then spread towards north, south and east.

Of the Nevalainen families moving along the eastern shore of the Pielinen lake, Olli Nevalainen stayed at Kylänlahti and founded the Nevala 1 estate there. He is one of the progenitors of Nevalainen´s living at the eastern shore of the Pielinen lake. His descendants have been the first targets of genealogigal research by the family society. The descendants of Olli Nevalainen are still living at Lieksa, Paalasmaa, Viekki, Höljäkkä, Poronsaari etc. Nowadays Nevalainen families have spread all over Finland, and beyond. For example, in the vicinity of Helsinki they amount to about a thousand.