AWS GovCloud (US) Region is an isolated Amazon Web Services environment used by US government agencies at the federal, state, and local levels, along with contractors, researchers, educational institutions, and other US customers.
In terms of boxes checked, GovCloud has received the following certifications:
An Agency Authorization to Operate (ATO) from the US Department of Health and Human Services (HHS) utilizing a FedRAMP accredited Third Party Assessment Organization (3PAO)
Federal Risk and Authorization Management Program (FedRAMP) at the Moderate impact level
U.S. International Traffic in Arms Regulations (ITAR)
The Federal Information Processing Standard (FIPS) Publication 140-2
Federal Information Security Management Act (FISMA, NIST 800-37)
DoD Information Assurance Certification and Accreditation Process (DIACAP), and
Department of Defense (DoD) Cloud Security Model (CSM) Levels 3-5
For more information on AWS's compliance with federal and other standards, see AWS's compliance page.
For installation purposes, GovCloud is treated like any other AWS region. Simply follow the steps for Installing GitHub Enterprise on AWS, being sure to select the 'us-gov-west-1' specific AMI ID.