Erie SeaWolves

The team was established in 1989 in Welland, Ontario as a New York–Penn League member, known initially as the Welland Pirates, playing their home games at Welland Stadium. After six challenging seasons, the team relocated to Erie following the exit of the previous baseball team, the Erie Sailors. This move eventually led the Frontier League-affiliated club to settle in Johnstown, Pennsylvania, where they became the Johnstown Steal (currently known as the Florence Y'alls in Florence, Kentucky). Before this, the Sailors had played in the New York–Penn League but relocated to Wappingers Falls, New York, becoming the Hudson Valley Renegades, due to the team's owner, Marvin Goldklang not upgrading Ainsworth Field to meet Major League Baseball standards.

After the civic government obtained an $8 million grant from the Commonwealth of Pennsylvania to construct UPMC Park (previously known as Jerry Uht Park), the Welland Pirates relocated to Erie. Although Erie did not have an affiliated baseball team in 1994, the city hosted an independent franchise in the Frontier League that revived the "Sailors" name. The SeaWolves eventually became the successor to several Erie-based baseball teams, including all iterations of the Sailors, with the New York–Penn League franchise now known as the State College Spikes.

On June 20, 1995, the SeaWolves triumphed over the Jamestown Jammers in their inaugural game in Erie. José Guillén, a Major League Baseball alumnus from the Dominican Republic, hit the game-winning home run for the team.

The SeaWolves served as the affiliate of the Pittsburgh Pirates from 1995 to 1998. In 1999, the Eastern League expanded by two teams, granting Erie one of the new franchises. As a result, the team moved up from the Short-Season A level to the Double-A level. Despite the change in classification, Minor League Baseball recognized the current SeaWolves organization as a continuation of the previous franchise. It allowed Erie to retain its New York–Penn League records and history. The Mahoning Valley Scrappers then joined the New York–Penn League as a separate expansion franchise, rather than as a continuation of the SeaWolves. After the promotion to Double-A, the team affiliated with the Anaheim Angels. In 2001, the SeaWolves switched affiliations to the Detroit Tigers, with whom they continue to partner.

As part of Major League Baseball's nationwide restructuring of Minor League Baseball in 2021, MLB reassigned the Erie SeaWolves to the newly created Double-A Northeast, a league that replaced the former Eastern League during the reorganization. The reorganization aimed to streamline player development, reduce travel, and improve facilities across the minors. As part of the changes, MLB eliminated dozens of affiliations, imposed stricter facility standards, and shortened the minor league season. The SeaWolves retained their affiliation with the Detroit Tigers and continued competing at the Double-A level. In 2022, Minor League Baseball reinstated traditional league names across all levels, restoring the "Eastern League" name for the SeaWolves' circuit.

On September 26, 2023, the SeaWolves completed a full sweep of the playoffs, capped off by a 10–0 win over the Binghamton Rumble Ponies in Game 2 of the Eastern League Championship Series, leading to their first championship title in franchise history.

On September 24, 2024, the SeaWolves completed their playoff run by defeating the Somerset Patriots 3-2 in Bridgewater, New Jersey. They won the Eastern League championship for a second straight year. In addition, they became the 11th team in Eastern League history and the first since the Trenton Thunder in 2007 and 2008 to repeat as champions.

Since joining the Eastern League in 1999, the Erie SeaWolves have experienced periods of competitive success and organizational development. While the team made several playoff appearances in the early 2000s, it did not secure a league title until the 2023 season.

Between 2018 and 2022, the franchise undertook a series of infrastructure improvements at UPMC Park, supported in part by a $12 million Redevelopment Assistance Capital Program (RACP) grant from the Commonwealth of Pennsylvania. These renovations aimed to meet updated Minor League Baseball facility standards and improve the spectator experience.

In 2023, Erie won its first Eastern League championship after sweeping the postseason. The following year, the team repeated as champions, becoming the first club to win back-to-back Eastern League titles since the Trenton Thunder in 2007 and 2008.

In 2025, the SeaWolves clinched their third consecutive first-half division title on June 21 with a 2–0 victory over the Bowie Baysox. Right-hander Austin Bergner, who had previously earned postseason recognition, started the game and allowed one hit over five innings.

These developments reflect the club's sustained presence in the Eastern League playoff landscape, supported by consistent player development and facility investment.