On 15 September 2017, the three-party coalition government collapsed after the departure of Bright Future over a scandal involving Prime Minister Bjarni Benediktsson's father writing a letter recommending a convicted child sex offender have his "honour restored".

[1] Bjarni subsequently called for a snap election,[2] which was officially scheduled for 28 October 2017 following the dissolution of the Althing.

A three-party coalition of the Independence Party, Viðreisn and Bright Future had been put together after the 2016 election; it held a narrow majority of one seat in Parliament.

Hjalti Sigurjón Hauksson was convicted in 2004 for multiple rapes of his stepdaughter from age five for twelve years.

Bjarni was informed of this in July 2017 by the justice minister, Sigríður Á. Andersen, also of the Independence Party, but Benedikt's support was not revealed by the government at first.

[5] Bjarni acknowledged the need for new elections, although the decision is made by the President, Guðni Thorlacius Jóhannesson.

Meanwhile, the Left-Green Movement sought an opportunity to govern for the first time since 2009 and implement ideologically leftist policies.

[13] The party's platform was broadly similar to that of its predecessor, but was characterised by observers in the media as being "populist",[14] with a particular emphasis on reform of the banking sector and firms such as Íslandsbanki.

The Left-Green Movement retained its position as the Althing's second largest party, increasing its representation by one seat to 11.

The Social Democratic Alliance saw a large increase in support, doubling its vote share from 2016, and entered the new parliament with seven members.

[18] Before meeting with Guðni, Left-Green leader Katrín Jakobsdóttir stated that she wanted to become Prime Minister, and did not exclude the possibility of cooperation with any party.

Logi Már Einarsson, leader of the Social Democratic Alliance, told Guðni it was natural for Katrín to receive the mandate to form a government if she so requested.

Jóhannesson on 2 November granted Katrín Jakobsdóttir, leader of the Left-Green Movement, the mandate to form a coalition between her party, the Progressives, Social Democratic Alliance, and Pirates,[33] the four having agreed in the morning to begin formal coalition talks,[34] which started the following day.

[44] At a meeting of Left-Green parliamentarians on 13 November, 9 voted in support and 2 against opening formal talks with the Independence Party, the two opposed being Andrés Ingi Jónsson and Rósa Björk Brynjólfsdóttir.