The History of the 1st Marine Division or the "Old Breed" in the final campaign of the Pacific War.
After many brutal struggles against the Japanese army on Guadalcanal, Solomon Islands, Cape Gloucester and Peleliu again, the Old Breed moved out, this time bound for Okinawa, a major island in the Ryukus only 350 miles from the southern Japanese home island of Kyushu. In the largest amphibious assault of World War II, Marine and Army units among them the First Marine Division landed on the Hagushi beaches on 1 April 1945. For most of April, the First was employed in a hard-driving campaign to secure the northern sections of Okinawa. On 30 April 1945, that all ended when the Old Breed went into the lines against the teeth of the Japanese defenses on the southern front.
The Division smashed up against the Shuri Line, and in a series of grinding attacks under incessant artillery fire, reduced one supporting position after another. As May wore on, heavy rains flooded the battlefield into a sea of mud, making life misery for all hands. meanwhile, Japanese kamikaze attackers exacted a fearsome toll from the supporting ships offshore. Finally, on 31 May 1945, Marines of the First completed the occupation of Shuri Castle, nothing more than a pile of rubble after so many days of unrelenting combat.
Under the overall command of Tenth Army, the Division continued the push south against the newly established enemy positions around Kunishi Ridge. Marine tank-infantry teams adopted a technique called "processing" to destroy Japanese positions with flame and demolitions. Finally, organized resistance ended on 21 June when the last Japanese defenses were breached. By now, many of the Old Breed's battalions had been reduced to nothing more than small rifle companies.