During this period, the powerful nations of the Iroquois Confederacy, based in New York, had maintained control of much of the Ohio Valley as hunting grounds by right of conquest after defeating other tribes.
By the terms of the 1768 Treaty of Fort Stanwix, the Penns were allowed to purchase the modern region from the Iroquois.
A 1769 survey referenced the future city as the "Manor of Pittsburgh".
Both the Colony of Virginia and the Province of Pennsylvania claimed the region under their colonial charters until 1780, when they agreed under a federal initiative to extend the Mason–Dixon line westward, placing Pittsburgh in Pennsylvania.
By 1815, Pittsburgh was producing significant quantities of iron, brass, tin, and glass.
Forbes began construction on Fort Pitt, named after William Pitt the Elder while the settlement was named "Pittsborough".
Today, Google, Apple, Bosch, Facebook, Uber, Nokia, Autodesk, and IBM are among 1,600 technology firms generating .7 billion in annual Pittsburgh payrolls.
The area has served as the long-time federal agency headquarters for cyber defense, software engineering, robotics, energy research and the nuclear navy. "Be it enacted by the Pennsylvania State Senate and Pennsylvania House of Representatives of the Commonwealth of Pennsylvania..the authority of the same, that the said town of Pittsburgh shall be...erected into a borough, which shall be called the borough of Pittsburgh for ever." The error was repeated commonly enough throughout the rest of the 19th century that the original pronunciation was lost and in 1890 the "h" was removed in order to make it easier to spell.
Michael Bezallion was the first to describe the forks of the Ohio in a 1717 manuscript, and later that year European fur traders established area posts and settlements.
During 1753–54, the British hastily built Fort Prince George before a larger French force drove them off.