Landis, who lived at a Sun City Center nursing home, died Monday, according to Donna Riley, his caregiver for the last five years. He had recently been hospitalized with a fever and low blood pressure, she said.
The remaining U.S. veteran is Frank Buckles, 107, of Charles Town, W.Va., according to the U.S. Department of Veterans Affairs. In addition, John Babcock of Spokane, Wash., 107, served in the Canadian army and is the last known Canadian veteran of the war.
The last known German World War I veteran, Erich Kaestner, died New Year's Day at 107.
Landis trained as a U.S. Army recruit at the end of the war and never went overseas. But the Department of Veterans Affairs counts him among the 4.7 million men and women who served during the Great War.
In an interview with the Associated Press last April, Landis recalled that his time in the Student Army Training Corps involved a lot of marching.
"We went to school in the afternoon and drilled in the morning," said Landis, who enlisted while in college in Fayette, Mo., at age 18.
"We got our uniforms a bit at a time. Got the whole uniform just before the war ended," Landis said. "Fortunately, we got our great coats first. It was very cold out there."
He told reporters in earlier interviews that he spent a lot of time cleaning up a makeshift sick ward and caring for recruits sickened by an influenza pandemic.
He signed up to fight in World War II in 1941, but at age 42 was rejected as too old.
Landis was born in 1899 in Marion County, Mo. He joined the Student Army Training Corps in 1918 and was released about a month after the war ended on Nov. 11 of that year.
He was a manager at S.S. Kresge Co., which later became Kmart, in Niagara Falls, N.Y., and Dayton, Ohio.
Landis retired to Florida's warmer climate in 1988 and lived in an assisted living center with his wife of 30 years, Eleanor. She turned 100 last summer.
His first wife, Eunice, died after 46 years of marriage. Landis had no children.
Associated Press