One of the last Japanese holdouts, Onoda continued fighting for nearly 29 years after the war's end in 1945, carrying out guerrilla warfare on Lubang Island in the Philippines until 1974.

Onoda was contacted in the jungles of Lubang by a Japanese explorer in 1974, but still refused to surrender until he was formally relieved of duty by his former commanding officer, Major Yoshimi Taniguchi, who flew from Japan to the island to issue the order.

[3] When Onoda arrived on Lubang, he encountered officers who outranked him and prevented him from carrying out his mission, which aided United States and Philippine Commonwealth forces in capturing the island when they landed on 28 February 1945.

[5] While in hiding, Onoda and his companions continued their mission, carrying out guerrilla activities, surviving on bananas, coconuts, and stolen rice and cattle, and on several occasions engaging in shootouts with locals and the police.

[6] They successfully evaded American and Filipino search parties, and attacked villagers whom they believed to be enemy guerrillas, allegedly killing up to 30 civilians on the island during their time in hiding.

Near the end of 1945, leaflets with a surrender order from General Tomoyuki Yamashita of the Japanese Fourteenth Area Army were dropped by air on Lubang.

On 19 October 1972, Kozuka was killed in a shootout with local police while conducting a recurring raid in which he and Onoda burned piles of rice harvested by the villagers, which they intended as a signal to fellow Japanese forces that their group was still alive and carrying out its duties on Lubang.

On 11 March, a formal surrender ceremony was held by Philippine President Ferdinand Marcos at Malacañang Palace in Manila, in an international media sensation.

[12] Onoda turned over his sword, a functioning Arisaka Type 99 rifle, 500 rounds of ammunition and several hand grenades, as well as a dagger his mother had given him in 1944 to kill himself with if captured.

[14] After the war, Filipino media interviewed villagers who had lived on Lubang during Onoda's time in hiding and alleged that he and his men had killed up to 30 civilians.

[15][16] In 1996, he visited the town of Looc on Lubang after his wife Machie (née Honoku) arranged a US$10,000 scholarship donation on his behalf to the local school.

[22][23] Chief Cabinet Secretary Yoshihide Suga commented on his death, saying "I vividly remember that I was reassured of the end of the war when Mr Onoda returned to Japan".