In the midle of the war, in 1915, Princess Catherine Radziwill published a book named THE ROYAL MARRIAGE MARKET OF EUROPE. So here is some contemporary speculation, an excerpt:
“The daughters of the Emperor Nicholas are perhaps the greatest matches in Europe at the present moment, if one takes into consideration the immense fortunes which they will bring to their husbands, in addition to their position, personal charm, and prestige.
But in the Royal marriage market they count but little in comparison with their brother, the little Grand Duke Alexis, about whose future wife people are talking already, notwithstanding the fact that he is but eleven years old and in very delicate health. Upon him rest the hopes of Holy Russia, and for him she prays every day in her numerous churches and shrines. He is a precocious, most intelligent child, the idolised son of fond parents, who for ten years waited in vain for the birth of a longed-for heir. Handsome, bright, clever, and wilful, he is, because of his physical weakness, the object of the most tender solicitude on the part of his father and mother, and it is probable that the Empress Alexandra is already wondering who will be lucky enough to win him for a husband when the time comes for him to look about for a bride. That he will marry young is certain, because, being an only son, it is most essential that the succession to the Throne should be assured in the direct line. It is but natural, therefore, that even so early this important question should be discussed both in private and in official circles. Russia would decidedly object to a German princess, even if it were likely the Romanoffs would turn their thoughts that way. A Spanish Infanta is out of the question. There remains, therefore, few others. The little Princess Ingrid, the daughter of the Crown Prince and Princess of Sweden, is one. She is about five years old at present. Or maybe one of her cousins, the daughters of Prince Charles and of Princess Ingeborg, may be chosen. It must be remembered that the Princess Ingeborg belongs to the reigning house of Denmark, and that Court has still much to say in Russian Court circles, and will have so long as the Dowager Empress lives. Perhaps the eyes of Nicholas II. may turn toward one of the little Greek princesses, of whom there are plenty, and who,through their Russian relationship, offer considerable advantages. There are nine of them, two daughters of the King, and their cousins, the children of Prince Nicolas and of Prince Andrew, all of whom promise to inherit the good looks of their respective mothers.”