British ICL Mainframes

International Computers Limited was Britain's dominant mainframe manufacturer, formed in 1968 through a merger of several British computing companies including International Computers and Tabulators. Its earliest mainframe family, the ICL 1900 series, was released beginning in the 1960s under the ICT name before the merger and became one of the few non-American competitors able to challenge IBM's System/360 in its home market. Rather than extend the aging 1900 architecture, ICL designed an entirely new machine from scratch for its next generation, unveiling the ICL 2900 Series on October 9, 1974. Both families represent the same national manufacturer's successive attempts to build a mainframe line independent of the American IBM-dominated market.