Armand Duplantis

Armand Duplantis first tried pole vaulting as a three-year-old at the family's home in Lafayette, Louisiana, and took to the event rapidly; he set his first age group world best at age 7, and his jump of 3.86 m (12 ft 8 in) as a ten-year-old surpassed the previous world bests for ages 11 and 12 as well. As of July 2015, he holds the world best in all age groups from age 7 to age 12; he held the age 13 record until it was broken in May 2015.

In 2015, his freshman year at Lafayette High School, Duplantis set national freshman records both indoors and outdoors and was named Gatorade Louisiana Boys Track & Field Athlete of the Year. As a citizen of both the United States and Sweden, Duplantis could have chosen to vault for either country internationally; in June 2015 it was announced that he had selected Sweden. Duplantis represented Sweden for the first time at the 2015 World Youth Championships in Cali, Colombia; he won gold on countback with a first-attempt clearance of 5.30 m (17 ft 4 ⁄2 in), improving his personal best by two centimeters and setting a new championship record.

Duplantis cleared 5.49 m (18 ft ⁄2 in) at a high school meet in Baton Rouge on 6 February 2016, setting a new age 16 world best, world indoor youth best and national high school indoor record; he was the first high school athlete to vault 18 feet indoors. Emmanouil Karalis of Greece, the same age as Duplantis, broke his world marks with a 5.53 m jump only one week later.

On 11 February 2017, at the Millrose Games, Duplantis jumped 5.75 m (18 ft 10 ⁄4 in) to set the World Indoor Junior Record. That mark was ratified by IAAF. A month later he improved to 5.82 m in the same facility at the New Balance National Scholastic Championships. That mark was not ratified due to incorrect peg lengths being used. On 1 April 2017, Duplantis jumped 5.90 m at the Nike Clyde Littlefield Texas Relays, improving his personal record and setting a new World Junior Record. The jump also became a Swedish senior record by 3 cm. While the IAAF recognized the record with Duplantis representing Sweden, on 2 December 2017, USATF also ratified Duplantis' mark as the American Junior record.

Duplantis was born into an athletic family; his American father, Greg Duplantis, who is of Cajun descent, is a former pole vaulter with a personal best of 5.80 m (19 ft ⁄4 in), while his Swedish mother Helena (née Hedlund) is a former heptathlete and volleyball player. His two older brothers, Andreas and Antoine, and his younger sister, Johanna, also took up sports; Andreas represented Sweden as a pole vaulter at the 2009 World Youth Championships and 2012 World Junior Championships, while Antoine dropped pole vault for baseball in high school before heading to Louisiana State University where he became the team's career hits leader in 2019.

On 17 September at the Rome Golden Gala Pietro Mennea Diamond League, Duplantis broke Sergey Bubka's outdoor world best of 6.14 m, with a second-attempt clearance of 6.15 m. Note that the IAAF does not recognize the indoor and outdoor pole vault as separate events; Duplantis already holds the world record at 6.18 m from his indoor clearance in February 2020.