Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
The Arrow Division was the military division of the North Sumatra branch of the Indonesian Christian Party during the Indonesian National Revolution. The division was established shortly after the independence of Indonesia to anticipate the incoming Dutch Army. The division was active in Tapanuli. The division became well known in Pematangsiantar due to the divisions' all out defense against the massive Dutch army that managed to broke through the fortifications of Medan Area Lembung.
Hakim, Lukman (2008), M. Natsir Di Panggung Sejarah Republik [M. Natsir In the History Stage of the Republic] (in Indonesian), Jakarta: Republika Publishing, ISBN9789791102438