Question

What event in Belgium is illustrated in this recruitment poster

Answer 1

Answer: The German Invasion.

Explanation: During WW1, Belgium was invaded by Germany in August 4th, 1914. The 1915 poster saying "Remember Belgium" and "Enlist today" is that of the invasion that happened.

Answer 2

It seems that you have missed the given image for us to answer this question, but anyway, I searched for it and found it. So based on the illustration, the event in Belgium that is illustrated in this recruitment poster is Belgium after Great Britain declared war. Hope this answers your question.