Fredsarkivet (The Peace Archive) collects, digitizes and makes available documentation about Swedish participation in international peace efforts throughout the ages. (in Swedish)
The archive is only available in Swedish. To get access to the archive you need to create a personal account with Fredsarkivet.
Some of the digital exhibitions are also made available in English.
Fredsarkivet is part of FBA - Swedish agency for peace, security and development.
Freely available within Sweden.