This book constitutes the refereed post-proceedings of the 4th IFIP WG 9.7 Conference on the History of Nordic Computing, HiNC 4, held in Copenhagen, Denmark, in August 2014. The 37 revised full papers were carefully reviewed and selected for inclusion in this volume. The papers focus on innovative ICT milestones that transformed the nordic societies and on the new ideas, systems and solutions that helped creating the welfare societies of today, in particular solutions and systems for public services, e.g., tax, social benefits, health care and education; solutions and systems for the infrastructure of the society, e.g., banking, insurance, telephones, transport and energy supply; and technologies and IT policies behind the major IT milestones, e.g., user centric innovation, programming techniques and IT ethics. They are organized in topical sections on IT policy, infrastructure, public services, private services, telesystems, health care, IT in banking, transport and IT technology.