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Pvt. Sonsire Triangle

Private Sonsire Triangle

This text is part of Parks’ Historical Signs Project and can be found posted within the park.

Private Frank Sonsire (1889-1918) died in World War I at the Battle of Argonne. Born in Rome, Italy, on January 7th, 1889, Sonsire came to America with his mother Sadie, and moved to 233 North 5th Street, in Williamsburg, Brooklyn. He joined the U.S. Army on May 28th, 1918, and went overseas on July 9. As a private in Company D, 316th Infantry, he fought in France at Avocourt and Proyon, both defensive operations in the Lorraine sector. He died in action on November 9, 1918, near Bois de Consemoye, in the Argonne region of France—three days after Germany formally requested a truce and two days before Armistice and the end of the war. He was 29 years old.

The Battle of the Argonne was one of the decisive and bloodiest operations against the Hindenburg Line, Germany’s stronghold in Western Europe. Argonne was the central bastion of the German line from the North Sea to Switzerland. American General John J. Pershing led the operation in three stages beginning on September 26, 1918 through the fall of 1918. On the morning of November 2, the German line was broken for the first time in four years. On November 6, Berlin formally requested a truce. More than 1,200,000 U.S. troops were used in the offensive, of which 117,000 were killed or wounded. World War I ended on November 11, 1918. Our current Veterans Day holiday was begun as a commemoration of the Armistice, or end of World War I.

This Williamsburg park is bounded by Union Avenue, Roebling Street, and North 11th Street. Williamsburg was once part of the Dutch town of Boswijck (or Bushwick). In 1802, Richard Woodhull, spurred by the idea of creating a residential suburb of Manhattan, began a ferry service from today’s Metropolitan Avenue to Corlear’s Hook across the East River. He purchased 13 acres of land surrounding the ferry and named the area Williamsburgh in 1810, after Colonel Jonathan Williams (1750-1815), the original surveyor of the site.

Woodhull went bankrupt one year later. But the idea of Williamsburgh was viable; Noah Waterbury built the neighborhood’s first distillery in 1819, and David Dunham (ca. 1790) began operating a steam ferry in 1827. Under Dunham’s direction, the village of Williamsburgh was incorporated that same year. By 1852, Williamsburgh’s population had grown to 31,000, and it was chartered as a city. The City of Brooklyn annexed Williamsburgh three years later, and dropped the “h” from its name.

This land came under Parks jurisdiction in 1938, and was named by a local law on June 6, 1938. The triangle today features London plane trees (Platanus x acerifolia), benches, and shrubs, and serves as a lasting memory to an immigrant who died in service of his adopted land.

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