Russian chemist, born in Tobolsk, Siberia, on February 7, 1834 and died January 20, 1907.
Mendeleev's most notorious contribution to mankind was the periodic table of the elements
(history and the table). This job took him most of his time and energy. Mendeleev led an unconventional life, at least for Russian standards in the second half of the 19th century. In this particular period Russia was under the reign of Czar Alexander II, who in contrast to his father's iron fist rule, was more liberal.
The first part of Dmitri Mendeleevs life is characterized by family turmoil: His father died early leaving his mother Maria alone with a huge family (Dmitri Mendeleev had 11 siblings). She found work in her family's glass-factory, which burnt down in 1848 leaving the family in a desolate position. After some years Dmitri, his mother and his sister Elizabeth moved to St. Petersburg in search of a better life. Mendeleev's mother and his sister died of tuberculosis just right after he was accepted in university. He married Feozva Nikichna in 1863 by arrangement of his older sister Olga, a circumstance which he did not really enjoy.
Luckily, Mendeleev found a safe haven in his work. He was a brilliant and recognized student and scientist. His work allowed him to travel around Europe, which at that point in time was scientifically flourishing. Back in Russia Mendeleev set out to bring knowledge to the common people. He would travel third class to talk to peasants about manuring strategies. This contact to the mass was regarded with some suspicion by the authorities, but since he was helping Russia rather than promoting dangerous ideas (such as democracy), they thought it was OK. As he grew older some of his statements became more and more political. Finally he was "promoted" from professor to minister of education - a nice way to keep a mischief away from the lecture halls.
Eventually his arranged marriage with Feozva collapsed, and in orthodox Russia you may divorce, but never ever marry again - that would be a criminal act of bigamy. He did marry again though, this time for love. Her name was Anna Ivanovna, and she had a deep influence on his life. The orthodox church - of course - did not like the idea very much but fortunately the Czar backed Mendeleev. "Mendeleev has two wives, yes, but I have only one Mendeleev" - and that was it.
He also did not care about his personal appearance. Stories went that he would have a haircut and shave only once a year. An eye-witness: "Every hair acted separate from the others." Work obviously came first for Dmitri Mendeleev.
Dmitri Mendeleev survived many bouts of tuberculosis in his younger years, and died peacefully during a reading of Jules Verne's Journey to the North Pole aged 73.