Carlsson was a member of the Riksdag from 1965 to 1996 representing the constituency of Stockholm County (until 1970 in the Lower House). He served as Minister of Education from 1969 to 1973, as Minister of Housing in 1973 and again from 1974 to 1976 and as Minister of Environmental affairs from 1985 to 1986. He served as Deputy Prime Minister from 1982 to 1986 and assumed office as Prime Minister of Sweden upon the assassination of Prime Minister Olof Palme in 1986.
Carlsson was born in Borås, Västra Götaland County (then Älvsborg County), Sweden and is the son of the warehouse worker Olof Karlsson and Ida, née Johansson. Carlsson has a diploma in business economics and a degree in political science from Lund University. In Lund he met with Tage Erlander, the Swedish prime minister and his aide Olof Palme, later to become Erlander's successor.
After finishing studies Carlsson got a job in Erlander's staff. In 1965, after completing further studies at Northwestern University in Illinois in the United States, he was elected member of the Swedish Parliament. In the same year, he also became leader of the Swedish Social Democratic Youth League. He had the following ministerial posts: Minister of Education 1969-1973, Minister of Housing 1973-1976, Deputy Prime Minister 1982-1986.
He was, together with Olof Palme, known as one of "Erlander's boys".
Following the assassination of Olof Palme in 1986, Ingvar Carlsson became the new Prime Minister or Statsminister and party leader. Together with Minister for Finance Kjell-Olof Feldt, the government turned a budget deficit of 90 billion SEK to a surplus of a few hundred billion SEK, which initially led to large investments and record low unemployment. As Prime Minister he also carried out a comprehensive reform of the tax system. But Sweden's economy began to deteriorate in the early 1990s. In 1990 the Carlsson cabinet resigned after failing to gain a majority for its economic policy agenda, but was reinstated immediately with a slightly changed agenda.
The Social Democrats lost the elections in 1991, but Carlsson returned to power after the elections in 1994. After three years in opposition and an election victory in the 1994 elections, Carlsson formed a new government. This government realigned its focus on cleaning up Swedish Government finances, and the task was assigned to the newly appointed Minister of Finance Göran Persson. The ensuing governing period was difficult and it was strongly criticized by trade unions and party members for government service cuts and tax increases that were instituted.
In August 1995, Ingvar Carlsson announced that he would resign as party leader and Swedish Prime Minister. His successor was long considered to be the then Minister of Equality and Deputy Prime Minister Mona Sahlin. However, due to the so-called Toblerone Affair, she took back her candidacy and also later resigned from the government. On December 5, 1995, the nominating committee proposed the Minister for Finance, Göran Persson, as the new party leader candidate. He was elected on March 15, of the following year at the Social Democratic Party Congress to Social Democratic party leader and on March 22, 1996 he was elected Prime Minister.
Ingvar Carlsson was Chairman of the inquiry after the Gothenburg Riots of 2001 to investigate the events. Their report was submitted to the Government on January 14, 2003.
Ingvar Carlsson was the Chairman of the Independent Inquiry into United Nations actions during the 1994 Rwandan Genocide. He is also chairman of the Bergman Foundation Center on Fårö.
With Shridath Ramphal, he was in 1995 one of the co-chairs of the Commission on Global Governance, which reported on issues of international development, international security, globalization and global governance.
His career has been shaped by the heritage of Olof Palme, with whom he worked closely, but his policies are more seen as being a continuation of the legacy established by Tage Erlander.
He is married since 1957 to librarian Ingrid Melander (born 1934), daughter of the wholesaler Sven H Melander and Gerda, née Eriksson. They have two daughters.
In 1989, Carlsson received an honorary doctorate from Lund University and in 1991 he received an honorary doctorate from Northwestern University.
Ingvar Carlsson is a big supporter of football teams IF Elfsborg and Wolverhampton Wanderers F.C..