Josiah Spode and Staffordshire
Around 1800, at his works in Stoke-upon-Trent, Josiah Spode settled the recipe that is still the basis of bone china.

Josiah Spode (1733–1797) was already a successful Staffordshire potter, known for blue-printed earthenware, when his works at Stoke-upon-Trent began experimenting with porcelain bodies in the late eighteenth century.
The recipe
Spode’s works combined calcined bone with Cornish china clay and china stone in proportions that are, in broad terms, still used: roughly half bone ash and the rest china clay and china stone. One widely quoted version gives six parts bone ash, four parts china stone and three and a half parts china clay.
The new ware was introduced in the 1790s — 1796 is the date usually given — and sold at first as “Stoke China”. After Josiah Spode’s death in 1797, his son Josiah Spode II developed the business and the material, and the name “bone china” came into use.

Why it spread so quickly
Spode’s body was white, strong and translucent, and — crucially — it could be made reliably. Within a generation the leading English factories had their own versions: Minton, Davenport, Coalport, Derby and Worcester were all making bone china in the early nineteenth century. Wedgwood made it from 1812 for a period, before taking it up permanently later in the century.
The Spode works received royal patronage in the early 1800s, and bone china became the material of British state dinners, embassies and great houses.
Why Staffordshire
The Potteries — the six towns that became Stoke-on-Trent — had everything the material needed: coal for the kilns, canals to bring Cornish clay and stone in and carry finished ware out, and a workforce whose skills were built over generations. Longton in particular became a town of bone china works, its skyline crowded with bottle kilns.

Look closer: what the name “bone china” does and does not tell you
The name records an ingredient and a history. It does not describe what the finished ceramic is like inside: in the kiln the bone ash reacts with the clay and stone and becomes part of new crystals and glass. What it is made of explains this.
Nor does it mean the ware is made in China. In eighteenth-century English, “china” simply meant porcelain, after the country it first came from.