Alexander Ypsilantis and the Etaireia had carried out an invasion of the Ottoman-dominated Danubian Principalities of the Ottoman Empire, which coincided with an uprising in Wallachia. Ypsilantis, a general in the Russian Army and aide-de-camp to Tsar Alexander I, had hoped that his actions would cause the Russian Empire to intervene on his behalf, but the Emperor, a leading proponent of the Concert of Europe, disavowed any relation with him and effectively gave the Ottomans the "green light" to march into the Principalities to deal with the insurrection. At the same time, Ypsilantis clashed with the Wallachian Pandur leader Tudor Vladimirescu, who was ultimately executed by the Etaireia and its remaining Wallachian supporters, leaving the Wallachian rebel troops to withdraw from the confl