The first event that the history of FedCSIS multiconference can be traced to, took place in 2005. It was the Scientific Session (Sesja Naukowa) organized within the scope of the 2005 Autumn Meeting of the Polish Information Processing Society.
In 2006 the first event under the name International Multiconference on Computer Science and Information Systems (IMCSIT) took place. It was co-located with the 2006 Autumn Meeting of the Polish Information Processing Society. The IMCSIT multiconference was co-located with the Autumn Meetings of the Polish Information Processing Society till 2010, when IMCSIT became an independent event under the new name (FedCSIS) and with a somewhat modified formula.
In 2007 computers holding data related to the 2005 and 2006 events have been sabotaged by hackers and the web sites for the two events have been lost. What remained intact, were the 2005 and 2006 procedings, which can be found in the links below.