Youppi!, a creation of Acme Mascots, Inc. (a division of Harrison/Erickson, Inc.), was commissioned by Montreal Expos vice-president Roger D. Landry.

Originally leased by the baseball team in 1979, the mascot was eventually purchased by the Expos and represented them until they moved to Washington, D.C., after the 2004 season.

[2] The orange, hairy giant was a popular figure at Olympic Stadium prior to the Expos' relocation to Washington, D.C. Youppi!

took a running leap, landing hard and noisily on its roof, and then sneaked into a front row seat.

was ejected by Bob Davidson,[5] though he later returned, confined to the home team's dugout roof, as Montreal eventually lost 1–0 in 22 innings.

was also a frequent joke punchline of notoriously sarcastic Atlanta Braves broadcaster Skip Caray.

on several occasions, including a prescient 1988 cartoon drawn at a time when the Expos were having a poor season and depicting then-general manager of the Canadiens Serge Savard receiving a phone call from Youppi!, presumably seeking employment.

On February 19, 2012, at the Canadiens' first home game after the death of Montreal Expos great Gary Carter, Youppi!

seemed to have fallen asleep in an ice machine in the Montreal Forum basement after a party celebrating the Stanley Cup win in 1993, and only emerged in the summer of 2022, when the thing was unearthed during renovations.

was working with the Expos, only 5 men portrayed the mascot: Denis Desaulniers, Jean-Claude Tremblay, Claude Hubert, Jean-Simon Bibeau and Sylvain Ouellette.

Inspired by the popularity and irreverence of the San Diego Chicken, Desaulniers auditioned for and received the part at 25 years old.

[16] At the time, Tremblay was doing corporate mascot gigs to make ends meet while working full-time at his brother's art shop.

Once the Expos' team discovered Tremblay's talents as a mascot, he was offered the opportunity to succeed Desaulniers.

As Youppi!, Hubert was responsible for the first and only incident wherein a mascot was expelled from a Major League Baseball game.

As Youppi!, Hubert hopped on top of the away team's dugout during an Expos v. Dodgers game and, following continued antics, was confronted by Tommy Lasorda.

)[18] After the scuffle began to escalate, Bob Davidson, the umpire during that game, made the decision to eject Youppi!, who was eventually readmitted following chants from the crowd and a promise to remain on the Expos' side of the field.

[19] This was not Bibeau's first experience with athletic recognition, as he was already holding a USA NCAA record for goals scored in a season while playing hockey with the Plattsburg Cardinals at this time.

During the Expos' two seasons in Puerto Rico, Ouellette proved especially valuable due to his Spanish proficiency and experience with Latin dancing and culture.