18th century

The following events occurred in the 18th century:
 * Quidditch is introduced to Australia.
 * The game Quodpot is created by Abraham Peasegood.
 * Several books and documents of "dubious scholarship" are published. Drawing partially from the writing of Salazar Slytherin, these works claimed that there were several signs that would identify a pure-blood child from infancy, such as early onset of magical ability, fear or dislike of pigs and Muggles, and resistance to common childhood illnesses.
 * A modern and complex plumbing system is installed at Hogwarts Castle, and bathroom facilities are created. Gaining knowledge that the secrecy of the entrance to the Chamber of Secrets is in jeopardy (as the room it was located in was to be turned into a girls' lavatory), Corvinus Gaunt, a student at the time, conceals it behind some new plumbing fixtures and a sink.

Decades

 * 1700s
 * 1710s
 * 1720s
 * 1730s
 * 1740s
 * 1750s
 * 1760s
 * 1770s
 * 1780s
 * 1790s