As the candidate of the two Christian Democratic sister parties, the CDU (of which he was a member) and the CSU, as well as the liberal FDP, Köhler was elected to his first five-year term by the Federal Convention on 23 May 2004 and was subsequently inaugurated on 1 July 2004.

Just a year later, on 31 May 2010, he resigned from his office in a controversy over a comment on the role of the German Armed Forces in light of a visit to the troops in Afghanistan.

[3] The owner and family of house occupied by Kohlers were sent to the Auschwitz concentration camp where they were killed by Germans serving in the SS.

[5] He studied and finally gained a doctorate in economics and political sciences from the University of Tübingen, where he was a scientific research assistant at the Institut für Angewandte Wirtschaftsforschung [de] from 1969 to 1976.

In that capacity, he served as a "sherpa" (personal representative) for Chancellor Helmut Kohl, preparing G7 summits and other international economic conferences.

[10] Köhler also played a central role in organizing the enormously expensive privatization of state businesses (VEB) in Eastern Germany.

[13] At the same time, he was widely reputed to clash with his American vice president, Charles Frank, and other EBRD officials reportedly complained about his temper and management style.

[16] At the time, he was one of three candidates for the IMF position, with Japan having put forward its former deputy finance minister Eisuke Sakakibara and several African nations backing Stanley Fischer.

[18] Before entering the office of managing director, Köhler had spent time in Indonesia during the 1997 Asian financial crisis and thereafter cited it as an example of the fund's tendency towards intrusive micromanagement.

[21] In 2001, Köhler recommended naming Timothy Geithner to replace Stanley Fischer as deputy managing director; instead, the US government under President George W. Bush successfully pushed for Anne O. Krueger to take the position.

[22] In order to accept his nomination as presidential candidate, Köhler left the IMF a year before his term was scheduled to end in May 2005.

[24] On 4 March 2004, Köhler resigned his post with the IMF after being nominated by Germany's conservative and liberal opposition parties (CDU/CSU and FDP) as their presidential candidate.

[30]Throughout his six years as president, Köhler "worked hard to put Africa on the top of Germany's political agenda", according to Deutsche Welle.

[33] On the eve of his resignation, Köhler presented his book Schicksal Afrika,[34] an edited volume on the continent's future with contributions from 41 authors, including former African presidents Thabo Mbeki and John Kufuor as well as Nobel Prize Literature Laureate Wole Soyinka.

[38] In October 2006, Köhler made a far-reaching decision by vetoing the bill which would transfer Germany's Air Safety Administration Deutsche Flugsicherung into private ownership.

[41] In March 2007, Köhler turned down a politically contentious request for clemency by Christian Klar, a terrorist from the far-left Red Army Faction.

[45] This came after German politicians criticised comments made by Köhler in relation to overseas military deployments:[46] In my estimation, though, we – including [German] society as a whole – are coming to the general understanding that, given this [strong] focus and corresponding dependency on exports, a country of our size needs to be aware that where called for or in an emergency, military deployment, too, is necessary if we are to protect our interests such as ensuring free trade routes or preventing regional instabilities which are also certain to negatively impact our ability to safeguard trade, jobs and income.

[55] Between 2010 and 2011, Köhler served as member of the Palais-Royal Initiative, a group convened by Michel Camdessus, Alexandre Lamfalussy and Tommaso Padoa-Schioppa to reform the international monetary system.

The Panel produced a final report with recommendations and thereby contributed in the making of the 2030 Agenda for Sustainable Development, which was adopted by all UN member states in September 2015.

Köhler took part in Namibia's 25th Independence Day festivities and represented Germany at President Ibrahim Boubacar Keïta's inauguration ceremony in Mali the same year.

[61] In 2017, Köhler was appointed by Secretary-General António Guterres as his new special envoy for Western Sahara, in charge of restarting talks between Morocco and the Polisario independence movement over the disputed territory.

[62] In that capacity, Köhler invited the foreign ministers of Morocco, Algeria and Mauritania as well as the secretary general of the Polisario Front in late 2018 for a meeting in Geneva to broker a settlement over the territory;[63] this marked the first time in six years that the involved parties met for negotiations.

[64] Köhler also worked for numerous charities and non-profit organizations, and held a honorary professorship at the University of Tübingen, his alma mater.