On 2 August 1914, the Red Cross Committee of Roeselare called on the local population for financial support and medical supplies. Their appeal did not go unanswered. Large supplies of donated medicines and bandages were stored at the Arsenaal, which also functioned as a field hospital with room for 500 wounded soldiers.
From September 1914 onward, the Arsenaal served as a refugee shelter. When many of Moorslede's citizens were made to leave their homes in November, they were received there. The refugees at the Arsenaal lived in abominable conditions, facilitating the spread of deadly diseases among them. The lack of hygiene quickly became unbearable. For fear of an outbreak of plague, the Germans eventually released the refugees from the Arsenaal and transferred them to the homes of civilians in the area.
At a later time in World War I, the Arsenaal was converted into a German military base, at the expense of a great number of refugees and patients. Over 300 German soldiers were stationed at the base. On 21 July 1917, the building was severely damaged in a British bombardment. The attic and ballroom were completely destroyed in the attack, and 25 soldiers were killed.