Al-Shabaab ƙawar Al-Ka’ida (Al-Qa’ida –AQ) ce kuma tana da alaƙa da sauran ƙawayen AQ, ciki har da AQ a ƙasashen Larabawa da kuma AQ ƙasashen Musulmi na yankin Maghreb. Al-Shabaab ɓangaren soja ne na tsohuwar ƙungiyar Somali Islamic Courts Council da ta kama iko da kudancin Somaliya a 2006. Tun ƙarshen 2006, al-Shabaab da sauran ƙawayenta sun ci gaba da ayyukan ta’addanci ta hanyar amfani da yaƙin sari-ka-noƙe da kuma ta’addanci kan gwamnatin riƙon ƙwarya ta Somaliya. 

Al-Shabaab ta kai hare-hare da yawa a Somaliya, da Kenya, da Uganda, da Djibouti. Al-Shabaab ce ta kai harin ƙunar-bakin-wake na 11 ga watan Yulin 2010 a Kampala. Harin da aka kai lokacin gasar Kofin Duniya, ya kashe mutum 76, ciki har da ɗan Amurka A Satumban 2013, al-Shabaab ta kai mummunan hari kan kantin sayar da kayayyaki na Westgate Mall da ke Nairobi. Ƙawanyar da ƙungiyar ta yi wa wurin tsawon kwanaki ta jawo kisan fararen hula 65, da kashe sojoji shida da ‘yan sanda, da kuma jikkata wasu ɗaruruwa. A Afrilun 2015, al-Shabaab ta kai hari da ƙananan makamai da kuma gurneti a Jami’ar Garissa da ke Kenya, inda suka kashe mutum 148. 

Ranar 18 ga watan Maris na 2008, Ma’aikatar Harkokin Wajen Amurka ta ayyana al-Shabaab a natsayin Ƙungiyar Ta’addanci ta Ƙasar Waje ƙarƙashin sashe na 219 na Dokar Ƙaura da Zama Ɗan Ƙasa, wadda aka yi wa kwaskwarima.  Daga baya, a ranar 19 ga watan Maris na 2008 Ma’aikatar Harkokin Wajen Amurka ta ayyana al-Shabaab a natsayin Ƙungiyar Ta’addanci ta Duniya bisa Umarnin Shugaban Ƙasa na Executive Order 13224 da aka yi wa kwaskwarima. Sakamakon haka, an hana al-Shabaab taɓa duka dukiya ko kadarori da ta mallaka da ke ƙarƙashin ikon Amurka, kuma an haramta wa dukkan Amurkawa yin hulɗar kuɗi da al-Shabaab. Laifi ne mutum ya samar ko ya yi yunƙurin samarwa ko ya taimaka wajen samar wa al-Shabaab kayan aiki.