I have searched on the internet about this but haven’t found a real answer. All I found said that the King wanted people to move north to the new mine, but it never said anything about the Sami.
I'm afraid that it depends largely on how we define the concept/ word 'freedom'. Anyway, the following is the basic outline of the circumstances on the Sámi or Finns/ Lapps in Norrbotten and further north in the end of the Middle Ages.
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As you know (?), Tälje charter (Tälje stadga) (SDHK 3558/ DS 2676), issued by King Magnus Eriksson who mediated the interest between the inhabitants of Hälsingland and the Birkarls active north to that region in 1328, is the first written evidence that specify the social position of the Finns/ Lapps (Sámi) as well as the trading with them as a kind of royal prerogative:
'It is also decreed that no one should disturb the forest, wandering people, called the Lapps in vernacular, in their hunting, but afore-mentioned Birkarls [is allowed] to take a visit to the Lapps to stay and exchange things......'
This attitude of Swedish ruler to the Finn-Lapp (Sámi) hunter-gatherer is similar to that of the high medieval king of Norway that claims the trade with Finns (Sámi) (finnkaup) to be a royal prerogative.
It became a basic principle of their dealing with the Sámi [and the middlemen of the trade, the Birkarls, assured their 'privilege' of trading by the Crown] throughout the later Middle Ages, and it was not until the the period during the Vasa dynasty in the 16th century that the king showed any renewed interest to regulate, or to draw more profits from the trade between the Sámi and the Birkarls, represented by the new systems (with old personnel as the same as the ex-Birkarls), such as the establishments of the Lapp bailiffs (Lappfogderi) and the royal fur chamber (Hansen & Olsen 2014: 232-41, especially 238-41). The oldest extant and detailed account of Lappmark, the tax register, dates only back to that period, the lreign of Gustav Vasa and the amount earlier accounts is really limited (at least than generally assumed).
The Birkarls (at least in the 16th century that we know from the extant source) were essentially local merchant elite family living on the both sides of Norrbotten (northern Gulf of Bothnia), and built extensive social networks on the northernmost part of the kingdom by intermarriage and other means (Miettinen 2016: 232-34). In other words, the trade with the Sámi was their traditional family business on frontier.
Swedish ruler had difficulty in enforcing stricter control on this relationship, however, namely on the following backgrounds:
In such a situation, I suppose that the Sámi in the 15th century Lappmark could generally avoid the excessive direct interference from the Swedish Crown, aside from the conflicts among the trading partners who came to deal with them.
There might have been another, more indirect interference, however (Harrison & Eriksson 2010: 46-49). Archaeologists saw the collapse of old stallo-type site and the restructure of Sámi occupying settlements (siidas) in the later Middle Ages, but they have not reached an consensus: While some scholars interpret it primarily as a possible impact of the demographic crisis posed by the Black Death from the south (as for the scant extant evidence on the outbreak of the Black Death in northern Sweden, see How did the black plague spread in the northern parts of Scandinavia?), others assume that the rise of new industry among the Sámi people, namely the reindeer herding, was chiefly responsible for this transition.
On the other hand, a contemporary evidence (household tax register) confirms the settlement of some Swedes in Norrbotten around 1400s, but their number was not so much, about 2,500 to 3,000 at most. This estimation is based on the household tax register during the reign of Erik of Pommerania, stating 300 household (corresponding ca. 2,000 inhabitant - each household had 6 to 7 members) payed the tax in coin (either of Stockholm or Åbo) in the southern part of the region and in kind, such as salmons and squirrels' skin, in the North (Westin (red.) 1962: 189-91).
AFAIK there was no known large-scale (armed) conflict between Swedish settlers and the Sámi (at least in Lappmark, not Finnmark area) in the 15th century, so the pressure from new settlers might have not been so serious.
Mining industry had not so developed in northernmost part of Sweden by the end of the Middle Ages, so main source of wealth for inhabitants in Norbotten must have been these kinds of natural resources, including those obtained from the trade with the Sámi. Though not so coherent, late medieval and early modern Swedish rulers generally also tried to assign Stockholm as a staple of such arctic natural products - in short, the inhabitants of Norrbotten were requested to trade their goods only in Stockholm, not freely to visit and to trade everywhere else. This royal policy certainly affect the economic development of Stockholm since the Later Middle Ages as well as the closer ties between Stockholm and smaller new cities around the Gulf of Bothnia. Some Birkarls also had their family members in Stockholm and/ or in some southern new cities to facilitate their 'family' business, and the natural products from Norrbotten (Cf. Miettinen 2016: 243), including the fur traded with the Sámi flowed by one of such trade-personnel networks into Stockholm, and further in European market.
[Added]: In sum, the Sámi people in the 15th century Lappmark could enjoy de facto freedom, but external authority saw their 'freedom' as a grant by the king of Sweden, and their hunting product was traded and transferred to outer market generally in accordance with their policy. In this sense, their livelihood itself were no longer free from such socio-economic ties with outer power(s).
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