1866

On May 10, 1866, Carol I of Hohenzollern-Sigmaringen arrived in Bucharest, the Romanian capital, and swore the oath of office in Parliament (painting by Theodor Aman, Aman Museum, Bucharest).
 

1877

On May 10, 1877, after parliamentary deliberations the previous day, Carol I proclaimed Romania’s independence. After 1947, the communists tried to erase any reminder of the monarchy from Romania’s history by "moving" the day celebrating independence to May 9th. The picture present Carol I during the War for Independece, 1877 (picture by Carol Popp de Szatmary, Library of Academy, Bucharest)
 

1881

Finally, on May 10, 1881, Romania was proclaimed kindom and Carol I was crowned as the first Romanian King (image from Suddeutche Zeitung)