Bronislaw Komorowski held a number of government posts after 1989
Bronislaw Komorowski, as Poland's parliamentary speaker, was thrust into the role of acting president after the death of Lech Kaczynski in a plane crash in Russia in April.
As Marshal of the Sejm - Poland's lower house of parliament since November 2007 - presidential powers were automatically transferred to Mr Komorowski upon Mr Kaczynski's death.
The 58-year-old historian and former defence minister was due to run in October's presidential election and opinion polls suggested he would have defeated Mr Kaczynski.
But he ended up facing Lech Kaczynski's twin brother, Jaroslaw, in an earlier vote.
Although he has remained the favourite, Mr Komorowski was unable to win the first round on 20 June outright.
But he won the 4 July second round with 53.01% of the vote, compared to 49.66% for Mr Kaczynski.
Mr Komorowski, the son of a count who grew up in poverty, represents Prime Minister Donald Tusk's ruling pro-business, pro-euro Civic Platform (PO).
A married father of five, he won his party's backing in March to be the PO candidate for the presidential election.
In the 1970s he was arrested several times by Poland's authoritarian government for taking part in anti-communist rallies.
He was also sent to an internment camp in the early 1980s while Poland was under martial law, according to his website.
Mr Komorowski has held several government posts since 1989, serving as a member of parliament since 1991 and as defence minister from June 2000 to October 2001.
He studied history at Warsaw University and later went on to teach the subject at a seminary.
Mr Komorowski was actively involved with the scouting movement, which he credits for introducing him to his wife.
In his first act after assuming the presidential duties, he declared a week of national mourning and urged Poles to set aside their political differences.