For nearly half a century, the Canadian province of Nova Scotia has been sending a gift to the people of Boston in the form of a Christmas tree. This annual tradition of holiday goodwill goes back to 1971, but the events that led to it is older still and was one of great tragedy.

In 1917, the port city of Halifax in Nova Scotia was a bustling scene of activity. The Great War in Europe was in its third year and Halifax’s strategic location in the Caribbean-Canada-United Kingdom shipping triangle made it an integral part of Allied war efforts not only during the First World War but the second one as well. The port’s protective waters sheltered convoys from German U-boat attack, while Halifax’s railway connection and world class port facilities enabled supplies, munitions and troops to be assembled from all around Canada and the US before they headed out into the open Atlantic Ocean and to the Western Front.

The Boston Common Christmas Tree—a gift from Nova Scotia to Boston. Photo credit: Keith J Finks / Shutterstock.com