Ro-41 belonged to the Kaichu K6 sub-class of the Imperial Japanese Navy, an evolution of the earlier K5 design built for greater range and diving capability. Mitsubishi Heavy Industries laid her keel at Kobe on October 6, 1942, originally designating her Submarine No. 207. She slid into the water on May 5, 1943, received the name Ro-41 that same day, and was commissioned into service by November. Powered by twin 2,100-horsepower diesel engines on the surface and 600-horsepower electric motors when submerged, she could make nearly 20 knots running on diesel and 8 knots underwater. Her surface range of 11,000 nautical miles at 12 knots gave her the endurance to operate across the vast distances of the Pacific theater.

Ro-41's most consequential action came on October 3, 1944, in the waters off Morotai Island, where Allied forces had established a major base for the coming invasion of the Philippines. The destroyer escort USS Shelton was screening a group of escort carriers when Ro-41 attacked. A torpedo wake was spotted at 1,500 yards -- close enough that evasive maneuvers came too late. While dodging one torpedo, Shelton was struck on her starboard propeller by a second. The damage was catastrophic: severe flooding doomed the ship. A fellow destroyer escort came alongside and evacuated the crew, but Shelton capsized and sank under tow. Thirteen of her sailors were lost. It was a sharp reminder that even as the war turned decisively against Japan, individual submarines could still exact a terrible price.

By March 1945, Ro-41 was operating under increasingly desperate orders. She departed Saeki on March 18 as part of a submarine force tasked with intercepting the formidable U.S. Navy Task Force 58. Some historians have speculated that Ro-41 may have sunk the American submarine USS Kete, which vanished south of Kyushu around March 20 while Ro-41 was in the same waters. But Ro-41 never reported sinking or even sighting an enemy submarine, making the attribution unlikely. On March 22, operating 320 nautical miles east of Okinawa, Ro-41 transmitted a message reporting that she had sighted an enemy destroyer. It was the last transmission the Japanese Navy ever received from her.

Later that same night, USS Haggard was serving as a radar picket 12 nautical miles ahead of Task Force 58. Her radar detected a surface vessel at 25,000 yards just before midnight. Haggard and the destroyer USS Uhlmann closed the range. The contact vanished from radar -- the submarine was diving -- but Haggard's sonar operators held the contact and Haggard attacked with depth charges. The submarine broached off Haggard's port beam, her conning tower breaking the surface. Haggard's 40mm Bofors guns opened fire immediately, and then the destroyer turned hard to port and rammed the submarine on her starboard side, just behind the conning tower. The impact crushed Haggard's bow but dealt a fatal blow to the submarine, which sank stern-first shortly after midnight on March 23. There were no survivors. On April 15, 1945, the Imperial Japanese Navy declared Ro-41 presumed lost with all 82 hands. She was stricken from the Navy list on May 25.