The first Marine operations took place in the Bahamas in March of 1776; four months after a resolution passed by the Second Continental Congress in Philadelphia established the United States Marine Corps. Today, volunteering for this branch of the military remains an honourable sacrifice of service to the United States. For non-U.S. citizens, however, joining the Marines is not as simple as showing up at the recruiting office.
Obtain U.S. citizenship. Military service is restricted to U.S. citizens and foreign nationals who have received a Bureau of Citizenship and Immigration Services Alien Registration Card (also known as a "Green Card.").
Go to the U.S. Citizenship and Immigrations Services website to establish the eligibility requirements for becoming a naturalised U.S. citizen. Some qualifications include sustaining permanent residency for five years---three years if the candidate is married to a U.S. citizen.
Apply for naturalisation. This process includes taking a test and filing the appropriate paperwork. People currently living in another country can contact the local U.S. embassy for assistance with these procedures.
Contact a USMC recruiting office once naturalised status is achieved. According to the website Military.com, "Only after immigration procedures are completed and an applicant is legally residing in the United States may an application for enlistment be accepted."