The 4th Brigade Combat Team, 10th Mountain Division (Light Infantry) officially activated at Fort Polk, Louisiana, 19 January 2005.

However, the Brigade's leadership immediately set to work to rapidly build combat power and capabilities in anticipation of deploying to support the Global War on Terror.

In the midst of preparing for deployment, elements across the brigade provided disaster response and relief within Louisiana to help mitigate the devastating effects of hurricanes Katrina and Rita during the fall of 2005.

Task Force Patriot assumed responsibility for eastern Baghdad – a heavily urbanized area encompassing 80 square miles and more than 2 million citizens.

Their mission was to conduct population-centric, combined-action counterinsurgency operations, building Afghan National Security Force capability and enhancing the effectiveness of provincial governments to create a more stable environment for transition and to defeat insurgency.