On Thursday, militants of Somalia's al-Shabab terror group launched a deadly assault on a college in eastern Kenya. Masked gunman stormed the grounds of Garissa University College, targeting Christians and taking hostages in scenes reminiscent of the horrific Westgate Mall attack which killed at least 67 people in 2013.

Thursday's attack comes at a time when al-Shabab is perceived to be losing ground among jihadists. The group is recovering from the death of its leader, Ahmed Abdi Gobani, in a U.S. airstrike last year and is potentially entering a stage in which it seeks to maintain relevance through high-profile violence.

Al-Shabab

Al-Shabab, which means "the youth" in Arabic, started as a small faction of radicalized Islamists in Somalia's Islamic Courts Union, an alliance of Sharia courts. The ICU took over Somalia's government in 2006, but the coalition was removed from power with help from the United States mere months later. Al-Shabab splintered off from ICU in the wake of the alliance's demise, and grew into what the Council on Foreign Relations describes as a "full-blown insurgency."

The group's well-established legacy of attacks in East Africa includes last year's assault on Kenya's Westgate Mall, brutal beheadings of suspected spies, as well as suicide bombings.

Ahmed Abdi Godane

In 2008, new leader Ahmed Abdi Godane rose to the helm of al-Shabab after the group's former head was killed in an American airstrike.

While The Telegraph once described Godane as "Africa's most feared militant leader," the little that is known about his personal history may seem at odds with that description at first sight.

Godane was thought to be around the age of 37 and may have grown up in northern Somaliland amid difficult circumstances. As The National Post notes , he had a background in accounting and also managed a grocery store with a friend, albeit one who he later ordered killed. He was also believed to be a lover of poetry .

Godane served as al-Shabab's spiritual and political leader from 2008 until his death in 2014. As a Washington Post profile from last year describes, he was a prominent force in taking the militant group from a loose network of hardliners into a relatively cohesive, and notably al-Qaeda-aligned, militant group. His leadership has been described as both brutal and controversial. The Post explains:

In areas that the militia controlled, Godane imposed strict Islamic sharia law enforced by public executions, amputations and stonings. The measures were so harsh, Hansen [an analyst specializing in al-Shabab] said, that even Osama bin Laden criticized him for going too far in implementing sharia and for killing other Muslims.

Under Godane's rule, al-Shabab steadily internationalized its attacks, hitting targets in Kenya and Uganda. Paul Hidalgo explains in Foreign Affairs that the group did not only plot against foreign targets but also stepped up its recruitment drive abroad in an effort to export its ideology.

The End Of Godane

After surviving previous attempts on his life, Godane was ultimately killed in a U.S. airstrike on Sept. 1, 2014. His death was seen as a major blow to the organization, and was predicted to have far-reaching implications.

Al-Shabab In 2015

Days after the death of Godane was confirmed, al-Shabab announced it had named Ahmad Umar its new leader.

Also known as Abu Ubaida, Ahmad Umar is a mysterious figure. He's believed to have joined the group in 2006 and issued vague threats to al-Shabab's enemies upon his appointment.

Umar inherited a group whose influence, territory and revenue were in decline.

Analysts described have described al-Shabab as in a state of disarray, desperate to keep apace with other rising terror groups. In a February 2015 propaganda video, the group issued a lengthy propaganda video that called on attacks at western malls, shot in a style that mimicked Islamic State produced videos.

While the decreased power of al-Shabab and death of its leadership were promising signs, experts also warned that the group could be anxious to maintain its power through continued violent attacks. As Paul Hidalgo warned in Foreign Affairs after the death of Godane: "Ahmed Umar will undoubtedly look to prove the skeptics wrong and unleash a series of attacks against the government in Mogadishu."

An earlier version of this story was published in September 2014 .