The United Service Organizations will be celebrating its 78th birthday on Monday, Feb. 4, 2019.

Better known as the USO, the private, not-for-profit organization works in cooperation with the Department of Defense to provide live entertainment and other services to members of the United States military and their families.

Born in 1941, the USO claims six different parents—the Salvation Army, the YMCA, the YWCA, Catholic Community Services, National Travelers Aid Association and the National Jewish Welfare Board. President Franklin D. Roosevelt asked the six agencies to combine their resources to boost the morale of troops fighting in World War II.

Although congressionally chartered, the USO is not a government agency, and has relied on charitable donations and the efforts of tens of thousands of volunteers for all of its nearly eight decades of history.

A new organization gives Hope to America's heroes

After being formed in 1941, the USO quickly became known for its live performances, which began with stateside military theaters spread throughout the country, and soon led to Hollywood stars heading overseas to entertain the troops.

Of those stars, the one most closely associated with the organization was comedian Bob Hope, who performed his first USO show only three months after its founding. Hope went on to entertain troops for the next 50 years, making his last trip overseas in 1990 during the Gulf War.

In 1997, the U.S. Congress declared Bob Hope the "first and only honorary veteran of the U.S. armed forces," in recognition of his half a century of entertaining those serving in the nation's wars. The USO Center at the Los Angeles International Airport also bears his name.

"The appearance of U.S. Department of Defense (DoD) visual information does not imply or constitute DoD endorsement.""The appearance of U.S. Department of Defense (DoD) visual information does not imply or constitute DoD endorsement."

Of course, no one could have originally imagined that Hope would eventually develop such a lengthy tenure as an ambassador for the USO—especially since the organization originally disbanded in 1947, after the Axis powers surrendered and ended WWII.

But in 1949, with America at the beginning of what would eventually become a lengthy Cold War, the USO's six original founding organizations decided to revive the agency. But due to funding issues, it wasn't until the Korean War began that the USO was back entertaining troops overseas, and the Defense Department earmarked $13 million for the organization's operations.

Yet the agency dealt with similar funding issues after the war concluded, and became dormant once more, remaining inactive until the U.S. entered the conflict in Vietnam.

Eventually, the USO received a government charter, and the organization also began placing more emphasis on improving the lives of military families, while still providing entertainment to soldiers as well.

Over 35 million troops served

Today the USO claims over 200 locations spread across 14 countries, including America, where it has a presence in 27 states. Over 30,000 volunteers help the organization realize its mission, as do the many musicians and entertainers who continue to perform live shows for military service members.

In 2016, during a gala event to celebrate the USO's 75th birthday, retired Army Gen. George W. Casey Jr. estimated that the USO had served more than 35 million Americans over the course of its history, according to The Providence Journal.

That service continues to take many forms, including family counseling for military members returning home from deployment, services for troops at airports as they travel to and from duty overseas and various programs that allow those deployed overseas to connect with their families stateside

As mentioned, the USO is a charity organization with a small paid staff, which relies on volunteers and charitable donations. To give the USO a birthday gift, head to their donation page and show your support.