Masjid Raya al-Mashun began construction on August 21, 1906, completed and opened to the public on September 10, 1909 AD At that time, the ruling in the King of Deli is the Sultan Mamun al Rasyid Perkasa Alamsyah IX. The entire cost of building a mosque, which is estimated to reach one million guilders is borne solely by the Sultan. This mosque is a royal mosque, therefore built very magnificent. At that time, the Sultan was principled, the grandeur of the mosque was more important than his own palace.
Thanks @gudanggarampro