Leo Fantl

Leo Fantl


Came to UK in June 1939 as a refugee from Czechoslovakia. Joined RAF age 18 and received technical training. Recruited by J Lyons & Co as Technical Trainee in the Planning Department in 1949, but was transferred to the LEO enterprise in 1950 to join Derek Hemy as a pioneer programmer. 

Despite a lack of formal training he became a first rate mathematician involved in developing mathematical software and doing ground-breaking work in the problem created by rounding errors. Played a major role in most of the early LEO applications including the tax tables for the UK Inland Revenue.

In 1960 he was seconded to work on LEO Computer’s first overseas venture, the joint establishment with Rand Mines of a LEO III computer bureau in Johannesburg. He spent much of his remaining career managing the computer operations of Rand Mines, by then the sole owners of the bureau. 

A brief biographical sketch of Leo Fantl can be found on page 202 of Peter Bird’s LEO: the World’s First Business Computer.

For more information on Leo Fantl, visit the History of Computing Project website.

Articles Written by Leo Fantl :




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