- "In 2175, less than ten years from when Savage conquers the world, the Earth is attacked by a warlike race of extraterrestrials from the planet Thanagar."
- —Zaman Druce[src]
Thanagar is the home planet of an extraterrestrial race known as the Thanagarians.
In Ancient Egypt, during the time of Khufu and Chay-Ara's first death, Earth and Thanagar aligned, and a meteor fell to Earth, which gave Hath-Set immortality and Khufu and Chay-Ara the ability to reincarnate upon death.  Another meteor fell in Harmony Falls in 1958, and Savage used it to mutate Tommy Fuller and Jefferson Jackson into Manhawks.
After Rip Hunter's team attempted to rescue Kendra Saunders in 1944, they discovered Savage stealing another Thanagarian meteor from the Nazis. Martin Stein was able to deduce that Savage wished to erase time going back to 1700 BC by detonating three meteors in three different time periods when Earth and Thanagar were aligned. Martin calculated that the two planets would be aligned in 1958, 1975, and 2021. Savage time traveled to 1958 to give his younger self Kendra's blood to detonate the first meteor, which was stopped by Mick and Ray. Savage then used the meteor from 1944 in his second ritual in Norway, 1975 but was stopped by Jefferson and Sara. The final meteor was collected by Savage in 2021, but flown into the sun by Rip Hunter.