After Somalia's defeat in the Ogaden War in 1978, he led a failed coup against President Siad Barre, marking the start of the Somali rebellion.

[3] Frustrated by the operation's failure and the SSDF's surrender to the Somali government, the Ethiopians jailed Yusuf until the Derg regime collapsed in 1991.

[10] Despite widespread opposition within the TFG and without cabinet or parliamentary approval,[11][12] Yusuf controversially requested Ethiopian troops to support his administration against the Islamic Courts Union during 2006.

By the end of the Ethiopian military occupation in December 2008, much of the country had fallen to the insurgency and Yusuf was threatened with international sanctions over his refusal to support national reconciliation.

[24] On 15 October 1969, while paying a visit to the northern town of Las Anod, Somalia's then President Abdirashid Ali Shermarke was shot dead by one of his own bodyguards.

His assassination was quickly followed by a military coup d'état on 21 October 1969 (the day after his funeral), in which the Somali Army seized power without encountering armed opposition – essentially a bloodless takeover.

[28] In 1978, together with a group of officials mainly from his own Majeerteen (Darod) clan, Ahmed participated in an abortive attempt to overthrow Barre's dictatorial administration.

He later learned of the failed putsch via a secured communication network, which contained a coded two sentence message from Col. Abdullahi Ahmed Irro reading "Wife Aborted", dated 11:00 am, 9 April 1978.

In 1992, he marshalled forces to successfully expel an Islamist extremist group linked to Al-Itihaad al-Islamiya that had taken over Bosaso, a prominent port city and the commercial capital of the northeastern part of the country.

[38] In 2000, Yusuf opposed the first attempt to restore a central state when the Transitional National Government (TNG) was created that year at a conference of elders.

Jama's close ties to the Mogadishu-based Transitional National Government alarmed Ethiopia, which opposed the TNG and was determined to remove it.

[42] During this period Abdullahi Yusuf's forces were responsible for the assassination of civic leaders in Puntland, most notably Sultan Hurre during August 2002.

Consequently, Ahmed along with his Prime Minister Ali Mohammed Ghedi and the Speaker of the Parliament Sharif Hassan Sheikh Aden helped to relocate the Transitional Federal Institutions (TFIs) from Nairobi to the Somali cities of Jowhar and Baidoa, where the TFG resided until the government eventually took control of Mogadishu.

[51][52] An African Union fact finding mission to Somalia in 2005 found that the overwhelming majority of Somalis rejected troops from neighboring states entering the country.

[53] Despite significant opposition within the TFG parliament,[54] President Yusuf made the widely unpopular decision to invite Ethiopian troops to prop up his administration.

[53] Due to a lack of funding and human resources, an arms embargo that made it difficult to re-establish a national security force, and general indifference on the part of the international community, President Ahmed also found himself obliged to deploy thousands of troops from Puntland to Mogadishu to sustain the battle against insurgent elements in the southern part of the country.

This left little revenue for Puntland's own security forces and civil service employees, leaving the territory vulnerable to piracy and terrorist attacks.

After the start of the new phase of the War in Somalia on 21 December 2006, the TFG, with the help of Ethiopian forces, wrested control of the southern part of the country and the capital, Mogadishu, from the hands of the Islamic Courts Union.

On 8 January 2007, as the Battle of Ras Kamboni raged, TFG President Ahmed entered Mogadishu for the first time since being elected to office.

Yusuf announced in a radio interview that “any place from which a bullet is fired, we will bombard it, regardless of whoever is there.”[59] Due to a lack of funding and human resources, an arms embargo that made it difficult to re-establish a national security force, and general indifference on the part of the international community, President Ahmed also found himself obliged to deploy thousands of troops from Puntland to Mogadishu to sustain the battle against insurgent elements in the southern part of the country.

This left little revenue for Puntland's own security forces and civil service employees, leaving the territory vulnerable to piracy and terrorist attacks.

Some of the more radical elements, including Al-Shabaab, regrouped to continue their insurgency against the TFG and oppose the Ethiopian military's presence in Somalia.

[71] On 21 December, Radio Garowe reported that 80 members of parliament held a conference in Baidoa where they all agreed that the vote of confidence in support of Hussein's government never took place.

"[72] On 24 December, the newly appointed Prime Minister Guled announced his resignation, citing that he did not wish to be "seen as a stumbling block to the peace process which is going well now.

[75] In December 2008, the TFG parliament moved to impeach President Abdullahi Yusuf, accusing him of being a dictator and an obstacle to peace.

[78] Yusuf stated that he had lost control of the country to Islamist insurgents,[79] and blamed the international community for its failure to support the government.

[80] While it was suggested that Ahmed's resignation added chaos to the country's political landscape as Ethiopia withdrew its troops, some diplomats opined that it might have improved the prospects of striking a deal with the more moderate Islamist insurgents.

[82] On 23 March 2012, relatives and Radio Mogadishu announced that Abdullahi Yusuf Ahmed had died at age 77 from complications due to pneumonia.

[83][84] Somalia's Transitional Federal Government, which Ahmed had co-founded, declared a three-day period of mourning for the late ruler and appointed a ministerial-level committee for the scheduled funeral proceedings.

[86] Ahmed was flown to the Aden Adde International Airport in Mogadishu, where the Bombay army band conducted a military funeral service in his honor and a Janaza prayer was dedicated to him.