Based on the text “Russians in Tlingit America”, By Dauenhauer and Black, the Tlingit were able to resist colonization post contact due to certain practices already in place prior to first contact. The Tlingit were a very war-like society and also had a class system not entirely unlike the Europeans. They had their own aristocrats and even had a system of slavery, so subjecting people was somewhat already familiar to them.
The Tlingit also had a habit of being very influential traders so it was not long after European contact that they managed to acquire enough firepower to be a credible treat to both other Alaska Natives and Europeans alike. The financial inability on the part of the Russians to secure firm trading relationships with the Tlingit when compared to the other European powers and the United States, really set them behind in terms of actual influence in the region.
Due to their political independence, the Tlingit were able to maintain their solidarity in both their religion and their society as a whole. It is because of their military prowess that the Russian American Company was never able to gain a great enough foothold in Southeastern Alaska and therefore the Russians were unable to make a profit when compared to the English and the Americans, who at that time were not wasting most of their resources trying to establish a permanent settlement in this part of the world, unless one counts Fort Simpson, established by the Hudson Bay Company in 1831. However since the Russians were more interested in making subjects of the Tlingit and the other native groups in the area, this put them at the center of conflict in this part of the world, while other colonial powers were there mostly to extract resources and trade goods.
The efforts on the part of the Russians to convert the Tlingit to Russian Orthodoxy were minimal at best and did not really set in until ironically well after the Russians had sold Alaska to the United States. Efforts by the Russians up until that point to convert the Tlingit were unsuccessful largely because the Tlingit were far more powerful and autonomous than the Russians would have liked to believe.
The battles of Sitka in 1802 and 1804 brought to light the fact that the Russians did not have the strength and resources to subjugate them because the Tlingit knew the interior of the mainland too extensively to allow themselves to be routed by the inferior Russian forces.After the Battle of Sitka in 1804, peace between the Russians and the Tlingit was uneasy, despite the treaties that were ratified after the battle there was still deep hatred between the Tlingit of other clans and the Russians, one example of this continuing animosity is when fort controlled by the Russians in Yakutat was destroyed by the local Tlingit clan and attempts to rebuild it were considered but deemed too expensive to the Russian government.
Despite many of the initial setbacks in their early colonial era, the Russians were able to make temporary allies with the Tlingit when it came to keeping other trading companies out of Alaska, companies like the Hudson Bay Company provide several such examples. Military force and knowledge of the land enabled the Tlingit to resist most forms of colonization but not all, some groups ended up trading far more to supplement themselves than they did in the pre-contact period. The new over-reliance on trading, combined with the inter tribal warfare, prevented the Tlingit from assembling the same strength that allowed them to destroy Yakutat. Therefore after the early 19th century they were never powerful enough as a single entity to push the Russians out of Alaska even though the Russians were incredibly vulnerable and weak after the Battle of Sitka.
As far as most Native groups are concerned, the warlike nature of the Tlingit was what allowed them to resist colonization so much more effectively when compared to other groups like the Unangan and Sugpiaq who had nowhere else to run when they were attacked by the Russians. The Tlingit were culturally and geographically situated to resist colonization far more than many of he surrounding native groups, many of which, with the exception of the Haida and Tsimshian, they viewed as inferior as people. The Tlingit view the Aleuts as slaves to the Russians and this reasoning is primarily why the Tlingit time and time again refused to let Russia claim ownership over them and their land. With these adaptations in mind, the Tlingits benefited largely from the presence of European powers, at least in the early days of colonization.