When was Lech Kaczynski sworn in as president of Poland?

Lech Aleksander Kaczyński (18 June 1949 – 10 April 2010) was a Polish lawyer and politician who served as the Mayor of Warsaw from 2002 until 2005 and as the President of Poland from 2005 until his death in 2010.

On 19 March 2005, he formally declared his intention to run for president in the October 2005 election.

In the first round of the elections he polled 33% of the vote, taking second place behind Donald Tusk. By the second round, however, he had gained the support of Radio Maryja, as well as of two other political parties besides his own: Self-Defence of the Republic of Poland, and the Polish People's Party.

Elected President of the Republic of Poland (he defeated the runner-up Donald Tusk by polling 8,257,468 votes, constituting 54.04 percent of the vote), Kaczyński assumed office on 23 December 2005, taking an oath before the National Assembly.