They are members of the Deutsche Eishockey Liga (DEL) since 2000 and play their home games at the Balver-Zinn Arena which is also known as Eissporthalle am Seilersee.

The Roosters are widely regarded for their fans and having one of the best atmospheres at home games in Europe despite having an arena capacity for just 4,967 spectators.

The club caused much controversy in 1987 when, under Heinz Weifenbach, a US$900,000 advertising deal was signed for former Libyan leader Muammar Gaddafi's The Green Book.

Recognizing the joy of the teenagers, the Canadians found some coaches, with Charles McCuaig later becoming a regular trainer.

After a long period of preparation, the first game against a Canadian youth team from Soest was on 8 March 1958 in front of 120 people.

However, Kaufbeuren waived their right to promotion, and Deilinghofen received the chance to play in Germany's top hockey league for the first time.

In 1986 ECD reached the semi-finals in the playoffs with stars like Jaroslav Pouzar and Martti Jarkko.

Due to the added expenses created by the addition of these star players, the team president, Heinz Weifenbach, looked for financial help in Libya, where Muammar al-Gaddafi agreed to pay if the team advertised his "Green Book".

One day later, on 9 April 1994, the ECD Sauerland Iserlohn Penguins were founded, but the peewee players didn't contract in, so the club's history was short-lived.

During the lockout season in 2004–05, Mike York and John-Michael Liles came to Iserlohn and helped the team reach 11th place despite still having the smallest budget in the league.

York signed with Iserlohn after his old college friend Bryan Adams, who was the captain of the Roosters, talked to him.

Twelve players left the club in the summer of 2005, but the Roosters were able to make some great moves on the transfer market with the biggest signings being former DEL top scorer Brad Purdie and former NHL player Mark Greig for two years.

After defeating the DEG Metro Stars 5–1 in the opening game of the season in 2006–07, the Roosters were in first place for one week for the first time in their history.

After again finishing another season in eleventh place, Ward then left Iserlohn during the summer of 2007 to be an assistant coach for the Boston Bruins of the NHL.

The line with Jimmy Roy, Pat Kavanagh, and Ryan Ready also helped the unexpected trip to the playoffs.

Due to the global financial crisis at that time, the Roosters announced that they would look for young, talented players instead of focusing on veterans for the 2009–10 season.