In response to unrestricted submarine warfare by the Germans, American President Woodrow Wilson delivered on April 18, 1916, an ultimatum that continued attack on American ships would provoke war. The next day, Neiu Nederlander President Theodoor van Rosevelt traveled to Washington to show his agreement. If the US went to war, the American Dutch would bravely join them.
The two nations had grown up alongside one another as Europeans colonized North America. The English threatened to eliminate the Dutch from their holdings of New Amsterdam when four frigates occupied the harbor. Director-General Peter Stuyvesant, after considering ceding the land in hopes of retaking it, decided to head off a Second Anglo-Dutch War and refused. After firing on the city, the frigates were rebuffed and returned to England empty-handed.
Since that time, New Amsterdam quickly expanded. Jews ousted from Brazil as Portugal retook Dutch conquests flooded into the city, and immigrants from all over the world were accepted. The economy flourished as pelts were harvested from the upper Hudson and established shipping. When the twin states of New England and Great Virginia declared independence from Britain, the Dutch granted support first financially and then through its impressive navy. When Napoleon conquered the Netherlands in Europe, Neiu Nederlands announced its own independence.
Relations between Neiu Nederlanders and Americans were amicable. They were particularly close with New England due to ties in shipping and manufacturing, although relations were at times strained while the United States to the south determining water rights of Lake Erie. When New England broke off trade with the US over slavery, the Nederlanders maintained a lucrative neutrality. The sudden surge of trade brought about a new golden age, which led to a great deal of corruption that responded in a powerful Progressive Movement, headed by the young Theodoor van Rosevelt.
Rosevelt was part of the wealthy and politically influential family that had begun with Claes Maartenszen van Rosevelt, who purchased a large farm on Manhattan Island that would translate into enormous wealth as the city grew. Theodoor was born in 1858 and struggled through his childhood suffering from asthma. He overcame the disease by determination and exercise with seeming limitless energy, features that would define his life. After his education, Theodoor traveled extensively to the American West as well as Dutch holdings in the Caribbean and South America. He returned and entered civil service, soon becoming Director of the Navy where he built a canal through Panama and led the Great White Fleet on its tour around the world. By 1910, he was elected President.
When war erupted in Europe, Rosevelt hoped to join quickly and use the impressive New Dutch fleet, but business was too good trading through the neutral Netherlands. Despite his extensive campaigning, it wasn't until the Americans threatened Germany that he finally gained the agreement of shipping interests who disapproved of attacks by uboats. In 1917, unrestricted submarine warfare resumed, and a joint declaration of war was announced. Thanks to Rosevelt's anticipation, New Dutch troops joined the front almost immediately.