Armistead wanted a flag the British would be sure to see. A Baltimore flag maker, Mary Young Pickersgill, was selected to make two flags. With the help of her 13-year-old daughter (Caroline Purdy) and two nieces, Pickersgill used English woolen bunting for the stripes and cotton for the stars.

The larger flag was so huge (about half the size of a basketball court) that Mary had to use the floor of a nearby brewery just to lay it flat. Today that large flag is owned by the Smithsonian Institute. She also made a smaller flag. Its whereabouts are unknown.

When she was an older woman, Caroline Purdy thought it might be important for people to know how her mother made the great flag. She wrote a letter to Major Armistead’s daughter, outlining all the details. Working hard to quickly finish the flag, Caroline said her mother often worked until midnight.

Pickersgill was paid $405.90 for the large flag and $168.54 for the smaller one. (Follow the link to view the receipt.) Her home in Baltimore is still standing and today houses The Star Spangled Banner Flag House Museum.

As Francis Scott Key and his two companions were detained on the British ship, the large flag flew over Ft. McHenry. Mary Pickersgill had made a sturdy flag. It would soon be put to the ultimate test.