(I mostly watch C-Dramas, and historical are my faves so I have a long list haha)
Ancient/Imperial China:
Nirvana in Fire - one of the best dramas ever made. Set in a fictional version of the Southern Liang Dynasty. The greatest revenge tv show ever written for Chinese (and honestly probably any countries') television. Superb acting, writing, set design, everything. 100% recommend.
Legend of Lu Zhen - Set during the Northern Qi dynasty. Follows the story a girl (Lu Zhen) as she works her way up from a merchant's daughter through the ranks of female official and also her love story with the Crown Prince.
Prince of Lan Ling - set during the Northern Qi dynasty (not related to Legend of Lu Zhen as a show, but is actually the history about 15-20 years after the end of Lu Zhen). Follows the story of a high ranked general (and prince of Northern Qi) and the last descendant of a mystical tribe of "Heavenly Maidens" as they try to strengthen their country and deal with the jealousy of other high ranked royals.
Legend of Zhen Huan - based on the life of Empress Dowager Niuhulu Zhen Huan (mother to the Qian Long Emperor) of the Qing Dynasty. A great drama, amazing acting and beautiful costumes/sets. Mostly set in the emperor's harem, so the one downside I would say is a bit too much in-fighting between the concubines, but it's a great show regardless.
Scarlet Heart - Beginning of the drama features time travel, but 99% of the show is set in the Qing Dynasty. Follows the history of the Yong Zheng emperor (this drama focuses on the Yong Zheng emperor while he is still a prince; Zhen Huan goes into his life while he is emperor). A relatively old drama, but one I'd call a classic. (Spawned the remake Scarlet Heart: Ryeo (korean version of the story))
Princess Wei Young - Set in the Northern Wei Dynasty. Story of an invaded kingdom trying to find out who framed her father (the king) and caused the demise of her country. Follows her story of revenge and also her falling in love with the prince of the nation that overtook her country.
Ten Miles of Peach Blossom - not really historical, but Wu Xia - still has a great ancient times feel to it along with love stories, fighting, and a bit of fantasy.
Beauties of the Emperor - follows the story of the beginning of the Han Dynasty. Story focuses on the life of Lu Zhi (later his empress) and her struggle being caught in the middle of the fight between Liu Bang and Xiang Yu (Chu-Han Contention)
Perfect Couple - Set during a fictional Ming Dynasty. Love story between son of a high ranked general and a peasant girl (masquerading as a noble girl) who is trying to reunite her adopted mother and her son.
Empress of China - THIS ONE IS A COMMITMENT. It's 90+ episodes (45 mins each) and follows the story of Wu Ze Tian (a very famous empress in Chinese history). Story was good, but honestly it wasn't good enough for a rewatch.
Early 1900s China: Both set during the Battle of Shanghai era (Japanese invasion of China) - Both currently also on Netflix with subtitles!
Rookie Agent Rouge - a really good spy drama set in the times leading up to the Communist Revolution in China. Lots of fun secret plotting/spy stuff with a perfect amount of melodrama and sass.
The Disguiser - much more serious of a drama, but still focused on the spy network in China during the time before the Communist Revolution . Great acting and intrigue, but was a bit too serious at times for me. Still a great watch
******
Moon Embracing the Sun - set during a fictional time in the Joseon dynasty. Ugh the feels. The lead actor (Kim Son Hyun) was amazing. A little bit of fantasy/witch craft involved. Very good drama.
Scarlet Heart: Ryeo - remake of Scarlet Heart. Set during the Goryeo dynasty. Story has a bit of actual historical accuracy, but is fiction overall.