Arthur Zimmermann was born in East Prussia in 1864. After diplomatic service in China he became German foreign secretary in November 1916.
In January 1917 he sent what became known as the Zimmermann Telegram to the German minister in Mexico. The telegram, which was intercepted by the British government, contained details of a proposed alliance between Mexico and Germany. The contents of this communication, which also included the suggestion that Germany and Japan would support a Mexican military attack on the United States, finally convinced President Woodrow Wilson that involvement in the First World War was inevitable. Arthur Zimmermann died in 1940.