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From the Middle Ages, there were water-powered knife-grinding workshops in Sheffield, using streams from the Pennine hills (the river Sheaf among others, which gave its name to the town). It became a steel manufacturing centre.

It produced Sheffield plate, a silver-plated metal.

A new process of crucible steel was discovered in the 1740s by Benjamin Huntsman, who needed better steel for clockmaking. He used coke, which had recently been discovered by Abraham Darby at Coalbrookdale. He corresponded with Matthew Boulton. The improved quality of steel contributed to the success of Harrison’s timekeepers.

Steel production at Sheffield was to dominate in the following period - the 19^th century.