[6] The attack was led by the Gruppi di Azione Patriottica (GAP) against the 11th company of the 3rd battalion of the SS-Polizeiregiment "Bozen" (Police Regiment "Bozen" from Bolzano[7]), a military unit of the German Ordnungspolizei ("Order Police") recruited in the largely ethnic-German Alto Adige region in north-east Italy, during the de facto German annexation of the region (OZAV).

At the time of the attack, the regiment was at the disposal of the German military command of the city of Rome, headed by Luftwaffe General Kurt Mälzer.

[8][9] The attack was performed while the Allies were fighting the third Battle of Monte Cassino, 118 kilometers (73 miles) away from via Rasella, to gain a breakthrough to Rome.

The GAP members, under the orders of Carlo Salinari (Spartacus) and Franco Calamandrei (Cola), were on Via Rasella during the passage of a company of the Police Regiment "Bozen", consisting of 156 men.

Eleven other partisans participated: The other members of the group were absent for various reasons: Lucia Ottobrini was ill, and Maria Teresa Regard was opposed to the choice of the place of the attack.