The Royal Exchange and its use as a centre for trade was inspired by the Brouse in Antwerp, which had made Belgium the financial capital of Europe. Ironically enough, Antwerp would be raided by the Spanish ten years later, losing the nation's wealth and allowing England to take over as the new financial power. Thanks again, Spain!
The main investor in the first Royal Exchange was a wealthy merchant named Sir Thomas Gresham. When the Exchange was built in 1570, it featured a grasshopper - the insect on Gresham's coat of arms - on the weathervane and a statue of Gresham in the open courtyard. The statue was the only thing in the Royal Exchange to survive the Great Fire of 1666.
Christopher Wren was hired to redesign London - a task about as big as being made Editor of the Internet - and he envisioned the Royal Exchange as the center of the city, with all of London sprawling out from it. The second Royal Exchange was open to the public from 1669 to 1838, when it was again consumed by fire. As flames licked the bell tower, the last song the bells chimes was the Scottish tune "There's Nae Luck Aboot the Hoose."
I'm sure the fact they kept playing loud Scottish folk songs was in no way connected to the place being set on fire.
The third and current Royal Exchange was built on the foundations of its predecessors and opened by Queen Victoria on October 28, 1844. Gresham's grasshopper returned to its place of glory, where it has remained since.