EPiServer was founded in 1994 by Mikael Runhem (formerly employed by Microsoft) as ElektroPost Stockholm AB, focusing on Internet-based electronic mail.
The company was founded with no external funding yet achieved strong growth already from the start thanks to the sale of e-mail solutions to Swedish companies and organizations. The collaboration with Microsoft on a mail system for VIP customers in Scandinavia was the beginning of an intensive partnership with the software giant. EPiServer built upon its success in e-mail and began to provide technology for building Web sites, a major early customer being the Swedish Stock Exchange.
With the aim of commercializing the Company's extensive technical know-how, the first version of EPiServer's CMS was introduced to a very immature market in autumn 1997; the platform solved problems that had not yet emerged at companies. In 2003, after a few years of relatively slow development, the Board decided to refine EPiServer's sales channel and divest EPiServer's consulting business. The purpose was to become a pure software company and avoid competing in any way with its partner companies. This focused EPiServer's operations to specialization in three areas: software, training and hosting.
In 2007, Mikael Runhem with family sold a controlling stake in EPiServer to a group of investors consisting of Amadeus Capital Partners, Northzone Ventures and Monterro Holdings, under the leadership of Peter Larsson (current Chairman of the Board). The new owners focused on growth through international expansion, investments in a broader product range, greater investment in marketing and expansion of the partner network. Mikael Runhem, with family, retained an ownership interest currently at 24.7 percent, and remained active in the company until 2009. In november 2010, IK Investment Partners ("IK"), a Pan-European private equity firm, acquired EPiServer from Amadeus Capital, Martin Bjäringer, Monterro Holdings, Northzone Ventures, Mikael Runhem and family and employees.EPiServer is now controlled by the IK2007 Fund. IK Investment Partners manages €5.7 billion in fund commitments.