Sir Henry Bessemer (19 January 1813 – 15 March 1898) was an English inventor, whose steel-making process would become the most important technique for making steel in the nineteenth century for almost one hundred years from 1856 to 1950. He also played a significant role in establishing the town of Sheffield, nicknamed ‘Steel City’, as a major industrial centre.

Bessemer had been trying to reduce the cost of steel-making for military ordnance, and developed his system for blowing air through molten pig iron to remove the impurities. This made steel easier, quicker and cheaper to manufacture, and revolutionised structural engineering. One of the most significant inventors of the Second Industrial Revolution, Bessemer also made over 100 other inventions in the fields of iron, steel and glass. Unlike many inventors, he managed to bring his own projects to fruition and profited financially from their success. He was knighted for his contribution to science in 1879, and in the same year was made a fellow of the Royal Society.