In the Afterword to Number the Stars Lowry explains how much of the story is true. Annemarie is a fictional character, but Lowry was inspired to create her by real stories that come from a friend of Lowry's, Annelise Platt (the novel is dedicated to her) who was a child in Denmark during the years of the war. Lowry was impressed by the stories of the Danes' bravery and devotion to their king.
Lowry goes on to outline some of the historical facts Number the Stars centers around. King Christian X was the king of Denmark when it was taken over by Germany in 1940. The country was too small to fight back without losing many people. Soldiers were all over Copenhagen. King Christian, however, did continue to ride his horse through the streets daily, without a bodyguard. Lowry adapted the story Mr. Johansen tells about the young man and the soldier from a document that survives from the World War II era. The Danes did sink their own navy in 1943. And on the Jewish New Year of 1943, the rabbi of the Copenhagen synagogue did warn those gathered that the Germans had their names. The rabbi had been given this information by one of the German officials, G.F. Duckwitz. Lowry commends this official for his action. A majority of the Jews were then hidden and helped to Sweden. It is also true that the handkerchief could have existed. Swedish scientists created a mixture of cocaine and rabbits blood that would temporarily kill dogs' sense of smell.
Lowry did research on the Danish Resistance. She found that most of the members were very young people, many of whom were killed by the Germans. During her research she discovered the story and photograph of a young man named Kim Malthe-Brunn. On this young man, Lowry based the character of Peter Neilsen. Lowry was struck by the letter that Malthe-Brunn sent to his family the night before he was shot. She includes in the Afterword a piece of that letter. It calls for dreams of creating "an ideal of human decency, and not a narrow-minded and prejudiced one."
By adding an Afterword to her novel, Lowry connects Number the Stars directly to the historical reality of World War II. She gives credit to the sources of her inspiration, demonstrating her respect for the people who actually experienced the events that the fictional characters of Number the Stars experience. An Afterword like this one is important to a novel based so heavily on historical fact. For the reader, the information that Lowry offers provides a dimension that the novel would not have had on its on—it makes real the struggles, risks, and deaths of a fictional group of people. In this way, the Afterword to Number the Stars acts as a memorial to all the real people who inspired the fictional characters of the novel.