Marie Louise went to Vienna after the fall of Napoleon I and took with her her personal jewelery, including the emarald parure. The parure stayed in the Habsburg family until 1953.
Then a Scandinavian decendant of the Habsburg family sold the diadem and kept the other pieces of the parure. They sold it to the famous Jewelhouse Van Cleef and Arpels.
They replaced the emeralds with turquoises and sold it to Mrs. Merriweather Post. Majorie Merriweather Post, is seen above, wearing the famous jewel. She donated the diadem to the Smithsonian Institution in 1966. See above in the pictures, update about the history
.The story about the wedding gift of Napoleon Bonaparte to Empress Marie-Louise Spätere Versionen der Smaragd Tiara | France Imperial Jewels History |Later Versions of the tiara