The Icelandic Alliance was a 51st century political coalition of nations based in Iceland. It was opposed by the Supreme Alliance of Eastern States, which brought it down by having its commissioner Ingrid Bjarnsdottir killed by the Peking Homunculus, an event which nearly precipitated World War VI.
One of the first four incarnations of the Doctor, who marched on Reykjavik with the Filipino Army, played a role in averting the war. He was able to do so using information provided by his fifth incarnation. (TV: The Talons of Weng-Chiang; AUDIO: The Butcher of Brisbane)
The Eighth Doctor, Fitz Kreiner, and Trix MacMillan once encountered several members of the Alliance, including the Lord General Razum Kinzhal and Colonel Gren de Schalles. By this account, the Time Agents originated as an Alliance force who policed the timelines to account for the damage done by Magnus Greel. (PROSE: Emotional Chemistry [+]Loading...["Emotional Chemistry (novel)"])