The Battle of Baiji was a battle that took place in Baiji, Iraq, lasting from late October 2014 to late October 2015. In mid-November 2014, Iraqi forces retook the city of Baiji, and re-entered the Baiji Oil Refinery. However, fighting continued in the region, and on 21 December 2014, ISIL forces took Baiji and put the Baiji oil refinery under siege once again, before Iraqi forces recaptured the city on October 22. It gave Iraqi forces complete control of the highway stretching from Baghdad to Baiji, and allowed Iraqi forces to use Baiji as a base for launching a future assault on Mosul.