‘It’s magic, extraordinary,” said star midfielder Melchie Dumornay, who was the hero with both goals.
“Since we were young we wanted to be there. We made it and now it’s like a dream come true.”
Dumornay, who has recently transferred to top French club Lyon, expects the achievement to have a long-lasting legacy.
“It is going to be positive, there will be more light on the team and it will give more opportunity to the young women in Haiti,” said Dumornay.
“We have quality, we have shown it and now it will inspire more young players.”
The celebrations will be “crazy” in Haiti, she added, as the team had been overwhelmed with messages over the past few days in the build to the winner-takes-all clash.
They can now look ahead to a dream World Cup match-up, taking on European champions England in their first match on July 22, before matches against China (July 28) and Denmark (August 1).
Haiti were good value for their win, in an eventful match, with 16 minutes of additional time in the second half.
Dumornay got a brilliant individual goal just before halftime, with a determined run from midfield then a crisp, angled finish.
Haiti could have sealed the contest with an 87th-minute penalty - for a shirt tug, which was awarded via VAR and looked a harsh call - but Chilean keeper Christiane Endler made a crucial stop.
Chilean midfielder Yessenia Lopez then saw her 25 metre effort hit the crossbar, before Dumornay booked their golden ticket with a second goal in the 98th minute.
Maria Jose Rojas finally gave the large bank of red shirts something to celebrate three minutes later, but it was only a consolation.
Haiti 2 (Melchie Dumornay 45′+1, 90′+8)
Chile 1 (Maria Jose Rojas 90′+11).
Halftime 1-0