This week we will continue the Story of the 105th’s harrowing exploits during the Battle of Saipan with Part two of our three part series. Today is the story of LTC William O’Brien. If you haven’t read part 1, I’d recommend you do so. Link here.
O’Brien was born in 1899 in Troy, NY just like the subject of Part 1, Thomas Baker. O’Brien was the Battalion Commander of 1-105 IN 27th ID New York National Guard. The 27th ID was mustered into Federal Service to fight in WWII in the Pacific Theater. There’s nothing that I could find that proved that these two Troy natives knew each other on a personal level since one was a private within the battalion and the other one was the Battalion Commander, but I have a feeling they knew each other ‘cus testicles that big would generate their own gravitational pull so they had to have known they were operating in the same AO.
On 20JUN1944, LTC O'Brien ordered 3 tanks to spearhead an assault on enemy fortifications. The Japs poured so much fire on the tanks they closed their turret hatches, this made the tanks lose their bearing and they started to fire on friendlies in their confusion. LTC O'Brien, ran across an open field while getting shot at by everything the Japs had, mounted a tank, and pounded on it with his pistol to attract the tank's crew and while fully exposed to enemy fire he personally spearheaded the assault and directed the Tanks’ fire until the enemy strong-point had been terminated with extreme fuckin prejudice.
While PVT Baker was single-handedly turning Japanese infantry into fertilizer, LTC O'Brien was ordered to capture a ridiculously fortified enemy ridge. As was his style, the good Colonel personally led the attack. When one of his platoons was stalled by stiff enemy resistance and suffered heavy casualties, O'Brien crossed 1,200M of sniper infested enemy territory to take charge. Think about that for a second, this fucking O-5 crawled, ran, jumped and juked his way across a fucking grid square all the while by being hunted by asshole snipers. In a textbook Battle Drill:1A, he left a base of fire element to pin the enemy while he personally led some men into a narrow ravine behind them, and killed or drove off all the Japanese at that strong point. His men captured 5 machine guns and one 77-mm artillery piece. O'Brien then organized for night defense and held his ground against repeated counter-attacks by bat-shit insane Japanese Forces.
At 0445 on 07JUL1944, the entire 1st BN of the 105th was hit with a sledgehammer of almost 5,000 pissed off, psychotic Japanese Infantrymen from three different sides. The Japanese engaged with a Banzai charge and with brutal close range fighting. The forward positions of 1-105th were overrun by the sheer weight of the enemy. In many sections of the line, the fighting devolved into brutal hand to hand violence. Even though his battalion suffered massive casualties and ammunition was nearly exhausted, O'Brien refused to leave his men and be evacuated. His job was to lead by example, and turning tail while his men died for him was not the legacy he wanted to leave on the battlefield.
O’Brien battled up and down the line from position to position, killing the enemy with a 1911 in each hand. Read that again. Imagine that. Imagine seeing your battalion commander fearlessly engaging in close range gunfights dual wielding dual pistols like Chow Yun Fat and perforating Japanese Infantrymen with 230gr projectiles.
His fearlessness and presence encouraged his men in their desperate last stand. During his courageous defense, O'Brien was shot in the stomach and severely wounded, but even then he refused to be evacuated. Eventually with his pistol ammunition completely spent, the colonel mounted an emplaced Jeep and got on the pintle mounted M2 .50 cal BMG and continued fighting as the survivors of the 105th broke contact in order to prepare for a counter attack. When he was last seen alive, O’Brien was still holding his position dumping .50 cal death and destruction into the horde of Japanese warriors storming his position. When American forces pushed the Japanese back and eventually retook the position where they last saw their Battalion Commander they found an Empty .50 cal with brass and links strewn all around and O’Brien’s body, still holding a bloody Japanese officer’s sword, surrounded by the ruptured corpses of over 30 Japanese soldiers.
This battle nearly broke the 1-105th and their sister battalion the 2-105th. They suffered 406 KIA and 512 WIA. Between the two Battalions they suffered an 83% casualty rate but they captured Saipan. In the 1-105th only a single lieutenant from B Co. survived from the entire Battalion’s officer cadre; every other officer was Killed in Action. In 2-105, every single company commander and the entire battalion staff were killed, and only the Battalion Commander of the 2-105 survived. Even still, the 105th managed to hold and capture Saipan and eventually, with resupply and reinforcements fought in Okinawa.
O’Brien died within hours of Baker in one of the bloodiest battles of the Pacific Campaign. They both died, giving their friends and comrades time to retreat and regroup and win. O’Brien, age 44, was posthumously awarded the Medal of Honor.
About the author: Andy, is a US Army Infantryman and your local Friendly Neighborhood Rooftop Korean. When he's not burning through his savings at the range, you can find him online sharing memes, playing video games, and writing stories about the baddest warriors throughout history. You can follow all of Andy's NSFW content at @call_me_ak on Instagram.