1750s

File:1750s montage.png|thumb|335x335px|From top left, clockwise: The Treaty of Madrid amends the pre-existing Treaty of Tordesillas (1494). Signed in 1750, this Spanish-Portuguese agreement, enabled Portugal to claim more holdings in what is now Brazil; Dzungar Khanate is captured by Qing forces in 1755, ultimately transferring Xinjiang into the hands of Han Chinese power – a legacy that continues to this day in modern-day China; A destructive earthquake and tsunami ravages the city of Lisbon in 1755, strongly influencing the studies of engineering, as well as philosophical thoughts on the Wes