Conversation so far:
How did Boris Yeltsin die?
Boris Yeltsin died of congestive heart failure
what caused Boris Yeltsin's death?
According to experts quoted by Komsomolskaya Pravda, the onset of Yeltsin's condition was due to his visit to Jordan between 25 March and 2 April.
where was Boris Yeltsin's funeral?
his body had lain in repose in the Cathedral of Christ the Saviour in Moscow
how many people attended Boris Yeltsin's funeral?
The church was open for viewing all evening and night, with around 25,000 people coming to pay their respects
what else happened during Boris Yeltsin's funeral?
the nation's flags were flown at half mast
what else is noteable about Boris Yeltsin's death
Yeltsin was the first Russian head of state in 113 years to be buried in a church ceremony, after Emperor Alexander III.
what else did Putin do?
President Putin declared the day of his funeral a national day of mourning

Question: what did yeltsin do to earn that?
Self-contained rewrite: what did yeltsin do to earn a national day of mourning?