The prince of Orange married the grand duchess Anna Paulowna, sister of Tzar Alexander I.
His first diplomatic work of importance was the negotiation of a marriage between the grand duchess Olga and the crown prince Charles of Wurttemberg.
King George married, on the 27th of October 1867, the grand duchess Olga Constantinovna of Russia, who became distinguished in Greece for her activity on behalf of charitable objects.
While still a girl she was connected with the Russian court, and became one of the leaders of the party that attached itself to the grand duchess (afterwards empress) Catherine.
He endeavoured to support his failing credit by a secret alliance with the grand-duchess Catherine, whom he proposed to raise to the throne instead of her Holstein husband, Peter, from whom Bestuzhev expected nothing good either for himself or for Russia.