The 85th Civil Affairs Brigade derives its lineage from the 362nd Civil Affairs Brigade (USAR), Dallas Texas, which was activated in August 1976 and inactivated in July 1978. The 81st Civil Affairs Battalion derives its lineage from the 29th Civil Affairs Company, which was activated in September 1945 in Manila, The Philippines. It participated in the Korean War before it was inactivated in December 1949. Most recently the 85th Civil Affairs Brigade was activated September 16, 2011 at Fort Hood, Texas.

The 85th Civil Affairs Brigade organizes, trains, equips, and deploys forces worldwide to conduct civil affairs operations to reduce and mitigate civil vulnerabilities for legitimacy and influence over relevant populations, in any environment, in support of Combatant Commanders and United States Ambassadors.

The Brigade operates within three distinct mission profiles:
Support to FORSCOM by deploying Civil Affairs units in support of Overseas Contingency Operations.
Provides a persistent Civil Affairs engagement capability to the Geographical Combatant Commanders, Army Service Component Commanders and United States Ambassadors in support of their theater engagement plans.
Deploy Civil Affairs Teams, Command and Control elements and Civil-Military planning elements to Corps and Joint Task Forces in support of Humanitarian Disaster Relief Operations and other contingencies as the Nation requires.