President Joe Biden has posthumously honored the service and sacrifice of the members of Hui Panala‘au, a group of men who courageously volunteered to live on uninhabited Pacific equatorial islands so they could become U.S. territories.

In a presidential message issued Thursday, Biden wrote, “From day one, my Administration has been committed to acknowledging the good, the bad, the truth of our past so that we can begin to remember and heal. A part of that effort includes recognizing the immense contributions and sacrifices of a little-­known group called the Hui Panala‘au.”

From 1935 to 1942, he said, the U.S. sent 135 young men, most of whom were Native Hawaiian, to colonize the uninhabited islands of Howland, Baker, Jarvis, Enderbury and Canton.

They spent months recording weather conditions and types of birds and marine life observed in the remote islands, cultivating plants and preparing landing strips, among other tasks.

With their help, President Franklin D. Roosevelt was able to issue executive orders proclaiming the islands under U.S. jurisdiction.

The National Oceanic and Atmospheric Administration shared that many of these isles were unnoticed until the 1930s, when military and commercial air routes between Australia and California brought them to the attention of the U.S. government.

The U.S. became interested in owning the islands with the arrival of World War II.

According to the U.S. Fish and Wildlife Service, the group was initially made up of recent graduates recruited from the Kameha­meha School for Boys and furloughed military personnel. Eventually, Kamehameha School alumni replaced the furloughed military personnel.

Biden said this was a story of “deep personal sacrifice and hardship.”

In addition to enduring harsh living conditions, the members of the Hui Panala‘au had limited access to emergency medical care.

Three Hawaiians lost their lives: Carl Kahalewai in 1938 to a ruptured appendix, and Joseph Keli‘ihananui and Richard Whaley in 1941 to an attack by Japanese bombers.

“For thousands of years, Indigenous peoples have persisted and survived — defined by strength, survival and a deep commitment to their heritage,” he wrote. “The Hui Panala‘au are a testament to this resilience and pride. I extend my deepest gratitude to each of the 135 members of the Hui Panala‘au and their families, especially to those who made the highest sacrifice. Their courage and service helped to advance the security and stability of our Nation.”

On Thursday, Biden also renamed the Pacific Remote Island Marine National Monument as the Pacific Islands Heritage Marine National Monument.

The monument encompasses about 490,000 square miles of open ocean, coral reef and island habitats, including the seven national wildlife refuges associated with Baker, Howland and Jarvis, as well as Johnston Atoll, Kingman Reef, Palmyra Atoll and Wake Atoll.