Why was a massive arch built at Grand Army Plaza?

In the 1880s veterans of the Civil War, organized into local “Grand Army” chapters, were calling for memorials to those who gave their lives defending the Union. Already under construction were monuments in Buffalo, NY; Hartford, CT; and at the Gettysburg battlefield cemetery. In 1882 the mayor of Brooklyn, which was still a separate city from New York, urged the construction of a monument to honor the patriotism and sacrifice of Brooklyn’s soldiers and sailors. The monument commission approved and then rejected a proposed 80-foot granite shaft with many sculpted figures.