Thousands of Twitter users are sharing the names and photographs of Jewish refugees who were killed in the Holocaust after their ship was turned away by both the United States and Canada in 1939.

The Twitter account t was created by Russel Neiss, a self-described Jewish educator, and Charlie Schwartz, a self-described rabbi and educator, to mark Friday鈥檚 International Holocaust Remembrance Day.

The story of the MS St. Louis is often referred to in history classes as an example of the consequences of discriminatory immigration practices. The launch of the Twitter account coincided with U.S. President Donald Trump鈥檚 executive order banning refugees and citizens from seven Muslim-majority countries.

More than 900 Jewish refugees fleeing Nazi Germany had boarded the Cuba-bound SS St. Louis, also known as MS St. Louis, in Hamburg on May 13, 1939.

After Cuba refused entry to nearly all of those on board, the ship鈥檚 captain appealed to the U.S. but President Franklin D. Roosevelt did not heed the call.

A group of prominent Canadians petitioned Prime Minister William Lyon Mackenzie King to allow the ship to dock in Halifax but his ministers recommended against it.

Although it wasn鈥檛 known at the time, Mackenzie King had written in his diary in 1938 that Canada must be kept free 鈥渇rom too great an intermixture of foreign strains of blood鈥� and that he feared there would be 鈥渞iots if we agreed to a policy that admitted numbers of Jews.鈥�

Canada鈥檚 racist immigration policies meant that fewer than 5,000 Jewish refugees were admitted between 1933 and 1945, according to Historica Canada鈥檚 .