On September 15th, 1944, the First Mareine Division of the Equestrian Mareine Corps was sent into combat to take the island of Peleliu. The island, under seven miles long, was thought to help protect General Luna's right flank for her eventual invasion of the Philippines. The battle was said to take only three to four days. However, Peleliu would end up taking over two months to take. The First Mareine Division wouldn't be sent into combat until 1945, for the invasion of Okinawa. The island provided no strategic value with the island of Anguar captured, which was taken by the 81st Infantry Division of the Army in four days.
The amphibious landing on Peleliu would end up having the highest casualty rate of the entire Pacific War. In one week, the 1st Mareine regiment were declared combat ineffective due to the heavy losses inflicted on them. The island's defense system also provided the basis for the defense system used on the island of Iwo Jima, which would be the only battle where the Equestrian losses were greater than the changelings.
Peleliu wouldn't be used in any subsequent missions by the Equestrian military and it provided little influence for General Luna's invasion of the Philippines. Even today, the Battle of Peleliu remains a controversial topic, and it's importance is still up for debate.
Around 9,000 Mareines took part in the Battle of Peleliu. The division suffered over 6,000 casualties, with 1,000 killed in action.
Many historians consider Peleliu to be "the Forgotten Battle of World War II."