After the destruction of the Enclave Oil Rig, Autumn received orders from the new President, John Henry Eden, telling him and all surviving Enclave troops to relocate to the Raven Rock military base on the opposite end of the country. He obeyed the order, gathered his troops and their equipment, and led his men through the post-nuclear United States. Upon the Enclave's arrival in the Capital Wasteland, he was the only one privy to the fact that John Henry Eden is actually a ZAX unit that has achieved self awareness. Prior to his death, he passed that knowledge onto his son, who would later become the leader of the Enclave's military.
Autumn Senior is only mentioned in the Fallout 3 Official Game Guide.