Bridal shows are a custom of choosing a wife for the head of state from among the most beautiful girls in the country. Unlike the traditional search for a bride from the different dynasties, the brides show was a second stage after the peculiar “beauty contest." The custom was originated in the Byzantine imperial court in the VIII century, and then in the XVI century became a Russian tradition.
They looked for the beauties all over the state. In Russia, the ambassadors were sent with instructions to search all over around the country. They were asked to rate "the charm of the face" and had at least three options for selection: the stature, the size of the head and the foot length (looking for Cinderella.) After that it was a process of thorough pre-selection of hundreds of girls. As historians tell us, at first the boyars met them and chose the best ladies from the best, corresponding to the next requirements: a future tsaritsa must be tall, healthy and beautiful, and it is desirable to have in her family many children - it ensured her fertility, and it is the essential consideration in Crown succession. The best girls met a monarch personally.
Of course, talking about the absolute impartiality of the selection made on such a “beauty contest “is impossible. All the brides were noblewomen, even if they were poor; unwanted ladies were eliminated for political reasons in the preliminary rounds.
In Russia, it happened that a tsar suddenly paid attention to objectionable female (for example, if close people to the throne, petitioned for their relative). In this case, everything was done to remove the bride with the “distance" under any pretext.

Why the highest representatives of the Russian authorities were not looking for a bride in “foreign" countries? "Encyclopedia of the rites and customs” indicates that Russian tsars chose brides from their country because they could not marry the daughters of foreign rulers from European knowledge of Russia as a wilderness inhabited by barbarians, and most importantly - because of differences in religious. This tradition was ended under the reins of Tsar Alexei Romanov. He became a widower at age 41, he chose the bride by himself, noticing her at a home of his, Boyar Artamon Matveeva, and the girl was a relative of Matveev. But they could not get married without a bridal show – so according to tradition they chose a bride, although the future royal bride already knew that she was destined to become a tsaritsa. So the daughter of a poor nobleman Natalia Naryshkina became the tsaritsa of all Russia, and soon the mother. Natalia’s son - Peter - became the first Russian Tsar Peter the Great, who opened the window to Europe, but he did not love his wife. His wife Evdokia was taking of monastic vows, she became the last of the Russian tsaritsa chosen from the daughters of Russian boyars and nobles. Since then, the Russian monarchs married foreign women and there were no longer bridal shows.