Alexandru Ioan Cuza was the first ruler of the United Principalities and of the national state of Romania. He actively participated in the revolutionary movement in Moldova and in the struggle for the unification of the Principalities. The double election of Alexandru Ioan Cuza as ruler of the two principalities meant a decisive success in the fight for the Union, on modern bases, of the Romanian national state. The system created was almost impossible to run through the Paris Convention. Cuza looked for a solution in diplomacy, and with the tacit support of France, he finally managed to achieve on December 23, 1861, the officialization of the Principality of the United Kingdom. On Sunday, February 8, 1859, there was a triumphant reception in Bucharest of the ruler of the Principality of Moldavia, recently elected ruler of the Principality of Wallachia, Alexandru Ioan Cuza. Mr. Unirii entered Bucharest via Băneasa, being welcomed with bread and salt by local officials and 100,000 people, almost the entire population of the Capital.