Gül was born in Kayseri, central Anatolia on 29 October 1950, the 27th anniversary of the proclamation of Turkish independence, also known as Republic Day in Turkey. His father is Ahmet Hamdi Gül, a retired air force mechanic, and his mother is Adviye Satoğlu.

Gül studied Economics at Istanbul University. During his graduate education, he spent two years (1976-78) in London and studied at the University of Exeter in the United Kingdom. Returning to Turkey in 1978, he became an instructor in the Department of Industrial Engineering at Sakarya University while working on his doctoral research on Turkey’s economic relations with other Muslim countries. He received his PhD from Istanbul University in 1983. Between 1983 and 1991, he worked at the Islamic Development Bank (IDB) in Jeddah, Saudi Arabia. He was conferred an honorary PhD degree from Amity University, Noida on 8 February 2009, and a LL.D from the University of Dhaka on 13 February 2010.

He was elected a member of the Turkish parliament for the Refah Partisi (RP, “the Welfare Party”) from the Kayseri electoral district in 1991 and 1995. During these years, he made statements about the political system of Turkey that was designed by Mustafa Kemal Atatürk and the Turkish National Movement, which included “This is the end of the republican period” and “The secular system has failed and we definitely want to change it”. These statements caused controversy when his candidacy for the 2007 presidential election was announced by Prime Minister Recep Tayyip Erdoğan.

In 1999, he kept his seat as a member of the Fazilet Partisi (FP, “the Virtue Party”) which was subsequently outlawed by the Constitutional Court for its violation of the Constitution. Its predecessor, the Refah Partisi, was also outlawed by the Constitutional Court for its violation of the Constitution, especially the principle of secularism. By this time, Gül had apparently moderated his views and was reportedly considered to be part of the Virtue Party’s reformist faction. Since 1993 in Ankara, he had been organizing an informal think-tank involving a group of Refah politicians who were discontented with the leadership of Necmettin Erbakan: these included Melih Gökçek, Bülent Arınç, Abdüllatif Şener, Recep Tayyip Erdoğan and Beşir Atalay. In August 2001, this group founded the Adalet ve Kalkınma Partisi (Justice and Development Party), a party which billed itself as a moderate conservative party in the European tradition. He was elected once again to represent Kayseri in 2002.

An interview he gave in 2002 summarizes his criticisms of the Refah Partisi under the leadership of Necmettin Erbakan and his portrayal of the AKP as a moderate party:

After the Justice and Development Party (AKP) won the most votes in the November 2002 general election, Gül was appointed Prime Minister, as AKP leader Recep Tayyip Erdoğan was still banned from participating in politics. After Gül’s government secured legislation allowing Erdoğan’s return to politics, the latter took over as prime minister on 14 March 2003. Gül was appointed deputy prime minister and foreign minister.

After becoming foreign minister in March 2003, Gül became the key player in Turkey’s attempts to receive an accession date for the European Union and in its attempts to improve relations with Syria and maintaining its relationship with the Turkic-speaking countries of Central Asia and the Caucasus. On 8 January 2008, Gül flew to the United States to meet with U.S. President George W. Bush and U.S. Secretary of State Condoleezza Rice.

Prime Minister Erdoğan announced on 24 April 2007 that Gül would be the Justice and Development Party candidate in the 2007 presidential election. Previously, there had been speculation that Erdoğan himself would be the party’s candidate, which had provoked substantial opposition from secularists. When a boycott of opposition parties in Parliament deadlocked the election process, Gül formally withdrew his candidacy on 6 May 2007. If elected he would be the first president to have been involved with Islamist parties. But a few days later, on 11 May 2007 when he inquired after the alterations to the Turkish constitution which now allowed the people to elect the president directly rather than a parliamentary vote, Gül announced that he was still intending to run.

On 28 August 2007, he was elected president in the third round of voting; in the first two rounds, a two-thirds majority of MPs had been required, but in the third round he needed only a simple majority. Gül was sworn in immediately thereafter. The process was a very low-key affair.

In September 2008 Gül became the first Turkish leader to visit Armenia where, in meetings with President Serzh Sarkisian, the two leaders formulated a solution to the tendentious problem of the genocide question, sparking a major debate in Turkey, but both the Armenian and Turkish parliaments refused to ratify the agreement. In November 2011, President Gül led a state visit to the United Kingdom as a guest of Queen Elizabeth II. The President met political and business leaders, visited the Olympic Park and was guest of honour at a state banquet at Buckingham Palace.

Gül has been a critic of Israel and Western countries which established relations with Israel at the expense of Palestine. After the Israeli raid on the MV Mavi Marmara in 2010, he advocated the complete ending of diplomatic relations with Israel, stating that “Israel will turn into a complete apartheid regime in the next 50 years if it does not allow for the establishment of an independent and proud Palestinian state with its capital in east Jerusalem. That is why we are exerting efforts to achieve a fair peace with a strategic point of view, which is to Israel’s own interests.”

On 31 December 2012, he stated with respect to the Arab spring and democratization of the Arab world: “But democracy is not only about elections. The task of creating essential democratic institutions – the rule of law, habits of accountability, gender equality, and freedom of expression and faith – still awaits these countries”.

In November 2013, Gül called on Muslim countries to fight against what he called Islamophobia during his address at the 29th session of the COMCEC in Istanbul. he said: