The ICSA History website provides a record of some the computer systems research projects undertaken in the Department of Computer Science at the University of Edinburgh prior to its assimilation into the Division (later School) of Informatics in 1998 and of projects undertaken since then in ICSA itself. Computer systems research began at the University of Edinburgh in the mid 1960s when the Computer Unit, established in 1963, was split in 1966 into the Department of Computer Science (DCS) and the Edinburgh Regional Computing Centre (ERCC). By 1971 a joint DCS-ERCC group had produced the Edinburgh Multi-Access System (EMAS), a general-purpose time-sharing operating system that was used to run a computing service at the University until 1992.This ICSA History website describes further examples of research projects in computer systems undertaken in the Department of Computer Science up until its assimilation into the Division (later School) of Informatics in 1998. Most of the people involved in projects that continued beyond 1998 became members of ICSA. Further information about the people involved in the early years of both research and teaching in computer systems can be found at: Early Teaching and Research in Computer Systems at the University of Edinburgh Computer Systems Group The Computer Systems Group was an informal group of academic staff in the Department of Computer Science who had interests in the design, capabilities and performance of computer systems. The group produced a series of Technical Reports in the years 1994-1998 and in 1998 became the core of the Institute for Computing Systems Archhitecture. The HASE Project 1990 - 2024 HASE is a computer architecture simulation and visualisation environment that has been used in teaching and research to create and run simulation models of a variety of computer architectures and to visualise their operation. This article was published on 2025-02-20