There is no a peace treaty for the Finnish Civil War in 1918. Officially no one has ended the war. Finland has done nothing after war, both side had not any conversation for the peace, probably some unofficial and secret deals have been done behind the scene with the elite. 
When you speak about Finnish, then are primarily speaking about Finnish people living in Finland or Finnish speaking people. Ofcource there is also Swedish Finns and so on. I think Finnish people is more official and modern term than Finns. There is lot of different people with different genealogy and history, all living together peacefully. It’s amazing to realize how our modern well being country works, it would look like very socialistic system.
We had a civil war called as Cudgel War (25 November 1596–1597), but also another Independence war in 1918, after our country has been founded in 1917. First time Finland stay in Sweden, but Finland became independent country after later war. It happened 300 years after first one. Similar war but the host country of Finland was changed from Swedish west to Russian east .
It’s not easy to be a rebel leader when lose a war, they aren’t worth of DNA test. They will be forget, and their family forgiven forever. Evidences will be demolished. 
REFERENSSIT YLE: Official war lost is 6 times over estimated
 Tuppu.fi: Offer you can’t refuse
 Wiki: Finnish Civil War 1918