Final answer:
Sir Christopher Wren was the architect who designed the rebuild of London after the Great Fire of 1666, with St. Paul's Cathedral being his most famous work, which is an example of the English Baroque style.
Step-by-step explanation:
The man responsible for the design and rebuilding of many structures in London after the Great Fire of 1666 was Sir Christopher Wren. He is widely recognized for creating the English Baroque architectural style and his most renowned work is the majestic St. Paul's Cathedral, which stands as a notable example of English Baroque architecture and the Classical tradition.
Wren's work followed the devastation of the Great Fire, and his architectural contributions were pivotal to the city's recovery and reconstruction. His designs were marked by heavy structures coupled with elaborate decoration, although they remained plainer compared to the contemporary Baroque of Europe, reflecting more Classical influences.
While Inigo Jones brought the Palladian style to England and designed notable buildings like the Queen's House at Greenwich, it was Christopher Wren's response to the Great Fire that left a lasting legacy on London's architectural landscape.