The Battle of Iwo Jima was a brutal, strategic clash over a tiny volcanic island.

Wars & Conflicts · Published 15 October 2026 Swipe more like this →

In short: In 1945, American forces invaded Iwo Jima, a small, volcanic island south of Tokyo. Expected to fall in four days, the battle instead became one of the bloodiest in Marine Corps history. The conflict revealed a shift in Japanese defensive tactics that forced the United States into a costly, month-long struggle.

The invasion of Iwo Jima, known as Operation Detachment, began on February 19, 1945, and lasted until March 16. Located about 760 miles from Tokyo, the island was deemed essential by the U.S. Joint Chiefs of Staff to provide a base for B-29 Superfortress fighters to support bombing raids on the Japanese capital. Admiral Chester Nimitz, who oversaw the Pacific campaign, prioritized the island as part of a strategic island-hopping approach to reach the Japanese homeland.

Japanese defense was led by Lieutenant General Kuribayashi Tadamichi, who arrived in May 1944. Departing from traditional, suicidal banzai charges, Kuribayashi ordered his estimated 21,000 troops to utilize a complex network of tunnels, caves, and fortified pillboxes. He instructed his men to remain hidden until American forces advanced inland, aiming to inflict heavy casualties rather than hold the coastline. This strategy proved highly effective, as the well-constructed defenses were resistant to all but direct hits from naval artillery.

Major General Harry Schmidt led the U.S. assault with approximately 70,000 Marines. Despite requesting ten days of naval bombardment to soften the island's defenses, Schmidt was granted only three days due to scheduling pressures for the subsequent invasion of Okinawa. The resulting battle was exceptionally intense, with both sides suffering over 20,000 casualties. The iconic image of Marines raising the American flag atop Mount Suribachi remains a defining symbol of the Pacific War, serving as a testament to the ferocity of the fighting and the Japanese military's resolve to defend the island.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• The Battle of Saipan: How a Pacific Island Changed the Course of World War II
• How a brutal island battle in 1944 shaped the outcome of the Pacific War
• The battle that taught the U.S. how to win in the Pacific
• The 82-day Battle of Okinawa was the bloodiest and fiercest conflict in the Pacific.
• How a remote Pacific island became the decisive turning point of the Pacific War
• The 1745 Jacobite rising was a desperate gamble that ended the Stuart dream forever.
• How a quiet Scottish island became the secret headquarters for World War II midget submarines
• How a Duchess survived the Wars of the Roses and beat a witchcraft trial
• A Duchess, a poisoned drink, and a judicial murder that defined a royal rift
• From the Stratford Festival to the screen: a life of Canadian craft
• Hitler's personal vendetta against Yugoslavia triggered a swift, multi-front Axis invasion in 1941.
• Did a French railway worker really father a child with Adolf Hitler during wartime?

More in UK & Ireland: wars · More in Wars & Conflicts · Latest · A–Z · All topics