Born in Moscow, Alexander Nikolaevich was the eldest son of Nicholas I of Russia and Charlotte of Prussia (daughter of Frederick William III of Prussia and of Louise of Mecklenburg-Strelitz). His early life gave little indication of his ultimate potential; until the time of his accession in 1855, aged 37, few imagined that posterity would know him for implementing the most challenging reforms undertaken in Russia since the reign of Peter the Great.
In the period of his life as heir apparent (1825 to 1855), the intellectual atmosphere of Saint Petersburg did not favour any kind of change: freedom of thought and all forms of private initiative were suppressed vigorously by the order of his father. Personal and official censorship was rife; criticism of the authorities was regarded as a serious offence.
The education of the Tsesarevich as future emperor took place under the supervision of the liberal romantic poet and gifted translator Vasily Zhukovsky, grasping a smattering of a great many subjects and becoming familiar with the chief modern European languages. Alexander's alleged lack of interest in military affairs (as detected by later historians) resulted from his reaction to the effects of the unsavoury Crimean War of 1853–1856 on his own family and on the whole country. Unusually for the time, the young Alexander was taken on a six-month tour of Russia (1837), visiting 20 provinces in the country. He also visited many prominent Western European countries in 1838 and 1839. As Tsesarevich, Alexander became the first Romanov heir to visit Siberia (1837). While touring Russia, he also befriended the then exiled poet Alexander Herzen and pardoned him. It was through Herzen's influence that the tsarevich later abolished serfdom in Russia.
In 1839, when his parents sent him on a tour of Europe, he met twenty-year-old Queen Victoria and both were enamored of each other. Simon Sebag Montefiore speculates that a small romance emerged. Such a marriage, however, would not work, as Alexander was not a minor prince of Europe and was in line to inherit a throne himself. In 1847, Alexander donated money to Ireland during the Great Famine.