Short answers, pulled from the story.
Neoclassical architecture began in the mid-1700s with early centers including Naples where Luigi Vanvitelli and Ferdinando Fuga worked by the 1730s. Giovanni Antonio Medrano built some of the first truly neoclassical structures in Italy during that same decade.
Karl Friedrich Schinkel built many notable neoclassical structures in Prussia including the Altes Museum in Berlin. His functional style provided the city with a distinctly neoclassical center despite Baroque dominance.
The British Museum construction spanned from 1823 to 1848. This period followed earlier works like the Theatre Royal Covent Garden which ran from 1808 to 1809.
Benjamin Henry Latrobe designed the Baltimore Basilica in 1806 as one of America's finest neoclassical examples. The structure remains one of the finest examples globally alongside international neoclassicism found in Washington D.C.
Excavations at Herculaneum began in the late 1740s but reached wide audiences only in the 1760s. Le Antichità di Ercolano Esposte distributed luxurious volumes showing genuine Roman interiors during this time.