Lotario is an opera seria in three acts by George Frideric Handel. The Italian-language libretto was adapted from Antonio Salvi's Adelaide.The opera was first given at the King's Theatre in London on 2 December 1729.

Adelaide of Italy, also called Adelaide of Burgundy, was Holy Roman Empress by marriage to Emperor Otto the Great. She was crowned with him by Pope John XII in Rome on 2 February 962. She was the first empress designated consors regni, denoting a "co-bearer of royalty" who shared power with her husband. She was essential as a model for future consorts regarding both status and political influence. She was regent of the Holy Roman Empire as the guardian of her grandson in 991–995.