"Siege of the Imperial City, 4E 174.[28] Lord Naarifin's Aldmeri army surrounds the Imperial City. Titus II breaks through the perimeter with his main army and flees north to Skyrim to join with reinforcements under General Jonna. The Imperial City soon falls and is sacked by the invaders. The Imperial Palace is burned, White-Gold Tower is looted, and the Aldmeri commit many atrocities among the city's populace." "Battle of the Red Ring, 4E 175.[28] Titus II splits his remaining forces into three hosts that surround the occupied Imperial City. After a long, bloody battle, the Aldmeri army in Cyrodiil is utterly destroyed and the Imperial City recaptured. Lord Naarifin is hanged from the top of White-Gold Tower and kept alive for thirty-three days. Despite the resounding victory, Titus II realizes that the Empire is too exhausted to continue fighting. Titus negotiates with the Thalmor and signs the White-Gold Concordat, a treaty that gives the Thalmor free rein to stamp out the worship of Talos in Tamriel, disbands the Blades, and cedes a large part of southern Hammerfell to the Aldmeri Dominion. Critics note that the terms of the Concordat are almost identical to those of the original ultimatum presented by the Thalmor prior to the war." Thats from UESPWiki. Does it sound like a clean war to you?