Brian Spencer Eifler is a United States Army lieutenant general who has served as the deputy chief of staff for personnel of the United States Army (G-1) since August 2024. He served as the first commanding general of the recently reactivated 11th Airborne Division and the Deputy Commander of Alaskan Command from 2021 to 2024. On 6 June 2022, USARAK reflagged to 11th Airborne Division as part of the implementation of the Army's arctic strategy. He has also served as the Deputy Commander for Operations of the 10th Mountain Division and Operation Inherent Resolve from July 2017 to November 2018.