Zenkaikon was formed by the merger of the anime and sci-fi con Zentrancon, and the anime con, Kosaikon, both in the Philadelphia area.

The decision to merge was originally proposed because both organizations wanted to strengthen and grow. Kosaikon and Zentrancon easily recognized that they each had a committed, experienced, and talented staff, and a combined effort would ensure a fun and exciting event for anime fans in the Philadelphia area.

Kosaikon held its first event in early 2003, where 75 individuals came together to celebrate their interest in anime. Over the next 3 years, it grew to over 400 attendees and gained popularity throughout the East Coast. Zentrancon's debut convention took place in October 2005. Over 350 people came to Philadelphia to watch anime and science fiction screenings, meet celebrity guests, and participate in video gaming.

In 2006 they put on their first event which was a tremendous success. They will be holding their second annual convention in King of Prussia, PA on October 13, 2007 in the Valley Forge Scanticon Hotel & Conference Center.

Zenkaikon is primarily staffed with folks from the 'Delaware Anime Society'(DE and Willow Grove, PA), with help from 'The Lost Otakus'(West Chester, PA). We also can't forget to mention the crucial help from numerous sponsers and outside assistance from brave souls willing to bear the burden of running a con for the enjoyment of Otaku everywhere.