This man was the first person to clear the height of 15 feet in the pole vault. He held the world record for 15 years, but he never won an Olympic medal. Who is he?

Cornelious (Dutch) Warmerdam??

You got it, man! Back in the late '60's when
I was a kid, Warmerdam was the track coach at Fresno State College. I lived close to the campus and would hang around on the sports fields with friends after school. Warmerdam
was probably in his 50's then, and once or twice I saw him demonstrating pole vault technique for his athletes. It was amazing!
Using a bamboo pole and wearing tennis shoes
he could still clear about 13 feet! He is argueably the greatest track athlete of all
time that never won an Olympic medal.